ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Computational Chemistry and Molecular Modeling  (2,412)
  • Wiley-Blackwell  (2,412)
  • American Association of Petroleum Geologists (AAPG)
  • 1980-1984  (1,667)
  • 1975-1979  (745)
  • 1930-1934
Collection
Keywords
Publisher
  • Wiley-Blackwell  (2,412)
  • American Association of Petroleum Geologists (AAPG)
Years
Year
  • 1
    Electronic Resource
    Electronic Resource
    Analysis of the space correlation factors in a MCSCF representation of LiH and Li2 molecules (1976)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 10 (1976), S. 151-162 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The space correlation factor is studied in LiH and Li2 molecules, using MCSCF wave-functions. The shape of the Fermi hole is related to the localization of molecular space orbitals, while the Coulomb hole study indicates the importance of symmetry properties of the molecular orbitals involved in excited configurations for the representation of the electronic correlation inside the chemical bond.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560100113
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Masthead (1976)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 10 (1976) 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560100201
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    The use of partitioning technique in the solution of operator equations for ionizations and excitations (1976)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 10 (1976), S. 233-247 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: An inhomogeneous operator equation is associated with the equations of motion for ionization- and excitation operators. The partitioning technique is applied to solve the equation. Formal expressions for the ionization- and excitation operators are obtained and examples of approximations to these are given.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560100205
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Exclusion principle and the symmetry adapted wave-functions (1976)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 10 (1976), S. 299-305 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Wave-functions of various spin-dependent and spin-free methods are examined from the point of view of the requirements of the exclusion principle and the spin projection. It is shown that the “two-rowed” or “two-columned” requirements of the standard Young tableaux are necessary but not sufficient to replace the “antisymmetry” requirement of a wave-function and to be regarded as exclusion principle. The symmetry adapted wave-functions which are constructed from the matric basis ers[λ] may not satisfy the exclusion principle and, hence, their usages are open to question. The appropriate symmetry adapted wave-functions which satisfied the exclusion principle are given for any pure spin state. We have also shown that the structure operators NirPir for bond functions are spin projectors in the Waller-Hartree double-antisymmetrized space only, and should not be used in the Hartree product space. Furthermore, if the corresponding matric operators PirNirPir are used in the Hartree product space, then the wave-functions thus constructed may not be antisymmetric with respect to the permutations of indistinguishable electrons.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560100209
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Light absorption at high intensities. Comparison of quantum theory and semi-classical results (1976)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 10 (1976), S. 359-377 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: An error in the author's previous treatment of the interaction of an absorber with high intensity light is noted. The correct development of Mower is applied to determine the amplitude of the initial state of the radiation-matter system. Comparison of the quantum theory solution for a damped absorber exposed to a square light pulse with the results of semiclassical theories based on the undamped optical Bloch equations is effected by determining the effective in- and out-of-phase components of the transition dipole response.In general, the out-of-phase (or absorptive) part of the transition dipole is zero at the outset and strongly time-dependent at short times, evolving to a steady-state value at longer times. For resonance radiation the system exhibits either overdamped irreversible decay or underdamped oscillations, depending upon the relative magnitudes of the incident light intensity and the radiative damping rate. Specific results are presented for a variety of limiting values of the physical parameters, including light intensity, damping rate, and amount of off-resonance.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560100213
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    The instabilities of the Hartree-Fock solutions and the lattice instabilities for conjugated hydrocarbons: The bond-order and bond-length alternations (1976)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 10 (1976), S. 917-935 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The instabilities, especially the singlet instabilities, of the conventional Hartree-Fock (HF) solutions for a variety of alternant and nonalternant hydrocarbons, some of which have been known to show lattice instabilities (bond-length alterations), are examined. The HF solutions for nonalternant hydrocarbons in the pentalene series larger than heptalene and [4n + 2]-annulenes larger than C22H22 are found to be singlet unstable and there appear new solutions lower in energy than the conventional HF solutions and characterized by charge-density waves exhibiting bond-order alterations. It is found that such symmetry-breaking solutions are energetically further stabilized by distorting the nuclear framework so that it may match up with the distribution of bond-order matrix elements of the charge-density wave, which means that in conjugated systems the singlet instability of the HF solution is always accompanied with the lattice instability. Further, it is shown that in conjugated systems, even when the HF solution is singlet stable, if it is not sufficiently stable as, for example, in pentalene and heptalene, there is every possibility for the occurrence of lattice instability. It is also shown that the singlet instability as well as the lattice instability arises from the existence of a sufficiently low-lying singlet excited state.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560100520
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    A comparison of different DODS methods when the number of electrons increases (1976)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 10 (1976), S. 961-966 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: We have performed RHF, UHF, UHF with subsequent spin projection, and EHF calculations for the π-electrons of some polyene chains of different lengths in order to investigate the relations among these methods when the number of electrons increases. Special attention is paid to the importance of spin projection for different energetic quantities.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560100606
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Generation of genealogical spin eigenfunctions (1976)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 10 (1976), S. 143-149 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A method is given for generating the Yamanouchi-Kotani genealogical spin eigenfunctions which requires neither storage of eigenfunctions for smaller numbers of electrons, nor summations of large order, nor explicit use of results from the theory of representations of the symmetric group. An explicit formula is given for the coefficients of expansion in terms of spin products.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560100112
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Some remarks on a double perturbation theory for molecular complexes (1976)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 10 (1976), S. 175-179 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560100115
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Reduced local energy as a criterion for the accuracy of approximate H2 wave-functions (1977)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 11 (1977), S. 59-71 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The goodness of the local fit of an approximate wave-function, \documentclass{article}\pagestyle{empty}\begin{document}$ \tilde \psi $\end{document}, to the exact function, ψ0, is \documentclass{article}\pagestyle{empty}\begin{document}$ |\tilde \psi - \psi _0 | $\end{document}. From this quantity the global accuracy of \documentclass{article}\pagestyle{empty}\begin{document}$ \tilde \psi $\end{document} is defined and a “working supposition” is presented, which quantitatively relates the global accuracy to the accuracy of expectation values. Two criteria based on the accuracy of the reduced local energy and the density respectively, are presented as alternatives to \documentclass{article}\pagestyle{empty}\begin{document}$ |\tilde \psi - \psi _0 | $\end{document}. The relative global accuracies of eight wave-functions for H2 are determined using the two criteria. The ‘working supposition’ is applied and predictions are made concerning the relative accuracies of the expectation values of the following operators: z2, r2, x2 + y2, 3z2 -; r2, ξ, rA-1, r12-1, and EL (the reduced local energy). The success rate is high (〉90%) except for those operators which are sensitive to interelectron coordinates or derivatives of the wave-function.
    Additional Material: 4 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560110106
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 11
    Electronic Resource
    Electronic Resource
    A new energy decomposition scheme for molecular interactions within the Hartree-Fock approximation (1976)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 10 (1976), S. 325-340 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A new method is proposed for the analysis of components of molecular interaction energy within the Hartree-Fock approximation. The Hartree-Fock molecular orbitals of the isolated molecules are used as the basis for the construction of Fock matrix of the supermolecule. Then certain blocks of this matrix are set to zero subject to specify boundary conditions of the supermolecule molecular orbitals, and the resultant matrix is diagonalized iteratively to obtain the desired energy components. This method can be considered as an extension of our previous method, but has an advantage in the explicit definition of the charge transfer energy, placing it on an equal footing with the exchange and polarization terms. The new method is compared with existing perturbation methods, and is also applied to the energy and electron density decomposition of (H2O)2.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560100211
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 12
    Electronic Resource
    Electronic Resource
    Molecular integrals of relativistic effects with Gaussian-type orbitals (1976)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 10 (1976), S. 379-379 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560100214
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 13
    Electronic Resource
    Electronic Resource
    A new approach to canonical orthonormalisation (1976)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 10 (1976), S. 413-418 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The canonical orthornormalisation procedure is derived through an integral equation with a finite rank kernel. Its optimal properties in connection with the problem of approximate linear dependence are established.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560100304
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 14
    Electronic Resource
    Electronic Resource
    The use of single exponential orbitals in one-center molecular orbital calculationsBased in part on a thesis submitted by Carl P. Miller in partial fulfillment of the requirements for the M. S. Degree, Mississippi State University, 1969. (1976)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 10 (1976), S. 455-460 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Single-exponential Slater type orbitals of the form ψ1 = (1 + L1(r, θ) + L2(r, θ) +…+ Ln(r, θ)) exp (- αr) are examined for their potential use as one-center molecular orbitals. These are then to be used as molecular fragments in a LCMO study. The system examined is HeH+ + with calculated energies and dipole moments being compared to the exact values. These functions behave best in the region of chemical interest (the bonding region) and thus demonstrate a possible usefulness in LCMO calculations and in the field of one-electron diatomics.
    Additional Material: 3 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560100308
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 15
    Electronic Resource
    Electronic Resource
    A density functional representation of quantum chemistry. II. Local quantum field theories of molecular matter in terms of the charge density operator do not work (1975)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 9 (1975), S. 855-870 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A comprehensive review of the attempts to rephrase molecular quantum mechanics in terms of the particle density operator and the current density or phase density operator is given. All pertinent investigations which have come to our attention suffer from severe mathematical inconsistencies and are not adequate to the few-body problem of quantum chemistry. The origin of the failure of these attempts is investigated and it is shown that a realization of a local quantum field theory of molecular matter in terms of observables would presuppose the solution of many highly nontrivial mathematical problems.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560090509
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 16
    Electronic Resource
    Electronic Resource
    Application of many-body green's functions to the calculation of molecular ionization potentials (1975)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 9 (1975), S. 901-916 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: We present a method for calculating the one-particle Green's function for molecules. The scheme is essentially that proposed by Schneider and Taylor [1]. The Green's function is obtained through the Dyson equation. Closed expressions result by using the functional derivation technique to truncate an infinite set of coupled equations. A physical interpretation of the approximation is given and a connection with the equations-of-motion method is pointed out. In a numerical application the ionization potentials are obtained for the molecules N2, H2O, NH3 and CH4.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560090512
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 17
    Electronic Resource
    Electronic Resource
    Ab initioLCAO-MO-SCF Calculation of chlorpromazine and promazinePresented at the International Symposium on Quantum Biology and Quantum Pharmacology, Sanibel Island, Florida, January 1975. (1976)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 10 (1976), S. 569-580 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Ab initio LCAO-MO-SCF Gaussian basis function calculations have been performed for chlorpromazine and promazine. By prescreening for the size of the integrals before calculation, it was only necessary to calculate 12 million out of the possible 38.5 million integrals for chlorpromazine. By a novel procedure of processing the integral tapes for the SCF it was possible to cut down significantly on the amount of time for the SCF. The SCF calculations converged smoothly for both promazine and chlorpromazine. There is a sizeable energy gap between the energy of the highest occupied molecular orbitals in these molecules (which is of the order of -0.3 a.u.) and the lowest unoccupied molecular orbital (which is of the order of + 0.15 a.u.). The gross atomic populations of chlorpromazine and promazine resemble each other and differ only somewhat on the carbon atom to which the substituent is attached and the carbons and their hydrogens adjacent to it.
    Additional Material: 10 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560100403
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 18
    Electronic Resource
    Electronic Resource
    A finite-difference approach to the electron correlation problem (1976)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 10 (1976), S. 643-658 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A variant of the transcorrelated method of Boys and Handy employing finite differences is presented. It is based upon the following two properties of the transcorrelated Hamiltonian operator C-1HC: (1) C-1HC possesses an energy eigenvalue spectrum which is identical to that associated with H itself; and (2) if \documentclass{article}\pagestyle{empty}\begin{document}$$ C \equiv \begin{array}{*{20}c} \pi & {e^{r_{ij} /2} } \\ {i 〉 j} & {} \\ \end{array} $$\end{document} then C-1HC is free of the singularities of H at the points where the interelectron separation rij is zero. A bivariational principle for approximating the eigenvalues and the left and right eigenfunctions of C-1HC is introduced and the resulting set of coupled integro-differential equations are solved in finite-difference form by means of a coupled self-consistent field, Newton Raphson algorithm. As a preliminary test of the method, a calculation of the ground-state energy of the helium atom is presented.
    Additional Material: 3 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560100408
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 19
    Electronic Resource
    Electronic Resource
    On the applicability of the selected valence electron split-shell method to ionic molecules (1976)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 10 (1976), S. 715-715 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560100413
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 20
    Electronic Resource
    Electronic Resource
    Best optimized one-electron wave-functions. III. Direct examination of optimization effectiveness (1976)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 10 (1976), S. 739-742 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The effectiveness of the recently developed method for optimization of one-electron wave-functions is directly examined by means of a simple procedure. By means of the same procedure the dependence of electron correlation on the nuclear charge and on the number of electrons is also investigated.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560100504
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 21
    Electronic Resource
    Electronic Resource
    On the scattering of slow protons by diatomic targets (1976)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 10 (1976), S. 37-56 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Inelastic collisions leading to rotationally excited molecular targets and involving protons as projectiles are theoretically examined from the point of view of both the scattering equations in the close coupling formalism and the interaction potentials between the partners.A phenomenological approach is suggested for constructing such interactions and computational results are reported for simple diatomic targets. The inadequacy of more traditional ‘static’ approaches, when called for explaining dynamic couplings with open channels and centrifugal effects, is also discussed.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560100105
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 22
    Electronic Resource
    Electronic Resource
    Hybrid Slater-Gaussian-type 1s orbitals for the 1∑g+ ground state of H2 and He2++ (1976)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 10 (1976), S. 781-789 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Introduction of noninteger powers of r (or the elliptical coordinate ξ) in the definition of the 1s AO is shown to give better approximate wave-functions for the ground states of H2 and He2++ than other functions of comparable complexity. This trend is examined for various definitions of hybrid Slater-Gaussian orbitals using a limited CI. The best optimized single-term expansion energy is only 0.000160 a.u. above the “SCF limit” for H2 at R = 1.4 a.u. and 0.000382 a.u. for He2++ at R = 1.3 a.u.
    Additional Material: 5 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560100509
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 23
    Electronic Resource
    Electronic Resource
    Generalized spherical functions in the theory of many-electron atoms (1976)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 10 (1976), S. 837-852 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A new method for finding non-relativistic and relativistic wave-functions of an electron moving in the field of a nuclear charge in the jj coupling scheme is proposed. It is based on the usage of generalized spherical functions. The mathematical apparatus necessary to find the expressions for matrix elements of the non-relativistic and relativistic energy or electron transition operators is developed. The formulas obtained for these matrix elements are more convenient than those usually used in jj coupling scheme; only their radial integrals and some phase multipliers depend on orbital quantum numbers.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560100513
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 24
    Electronic Resource
    Electronic Resource
    I. Lineare Fehlerminimisierung Ein Verfahren zur Eigenwertberechnung bei Schrödinger-Operatoren (1976)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 10 (1976), S. 873-885 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A variational principle is derived from the spectral theorem of self-adjoint operators. The principle allows to calculate simultaneously upper and lower bounds for each point of the spectrum. For Schrödinger operators this method of error minimization is reduced to a series of matrix diagonalizations using an iterative process and is linearized in this way. The convergence of this method and the equivalence with the nonlinear problem of variation are proven.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560100516
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 25
    Electronic Resource
    Electronic Resource
    II. Eigenwertberechnung beim Dreikörperproblem (1976)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 10 (1976), S. 887-899 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The convergence and the quality of approximation of the variational method developed in part I are tested using the He atom as an example. For the three-body problem the inner products and the norms were explicity expressed as functions of the optimization parameters. The method permits calculation of upper and lower bounds for the ground state of helium.
    Additional Material: 4 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560100517
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 26
    Electronic Resource
    Electronic Resource
    On the solution of the N-completeness problem (1976)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 10 (1976), S. 937-940 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A solution is given for the problem of N-completeness which arises in practical calculations for many electron systems because of the necessity of employing a finite basis set of antisymmetric two-particle functions.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560100602
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 27
    Electronic Resource
    Electronic Resource
    The convex structure of electrons (1977)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 11 (1977), S. 907-916 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560110604
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 28
    Electronic Resource
    Electronic Resource
    A linear combination of molecular orbital formalism (1977)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 11 (1977), S. 1001-1004 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560110612
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 29
    Electronic Resource
    Electronic Resource
    Errors in the calculations of first-order and second-order energy perturbationsResearch Supported by NATO Research Grant No. 930. (1976)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 10 (1976), S. 249-259 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: We consider the calculation of first-order and second-order atomic and molecular properties from approximate ground-state wave-functions by using variational procedures for solving the first- and second-order perturbation equations. We evaluate the errors in the final results due to the error in the unperturbed wave-function and to the errors caused by the approximations in solving the perturbation equations. By combining slightly different results we can eliminate all first-order errors. Our analysis covers situations where perturbation expansions of the error in the ground-state wave-function are not feasible and it includes the effects due to approximations in solving the perturbation equations.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560100206
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 30
    Electronic Resource
    Electronic Resource
    Symmetry property of Löwdin's “alpha” function (1976)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 10 (1976), S. 1081-1082 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560100621
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 31
    Electronic Resource
    Electronic Resource
    A model for the helix-coil transition of DNA (1977)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 11 (1977), S. 49-57 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The helix-coil phase transition of DNA is studied through a model equivalent to the one used in the theory of superconductivity. A distribution function for the excitations analogous to the usual Fermi function is obtained which depends on the parameter T0, the maximum temperature at which all pairs of bases are bonded. The expression for the number of unbonded pairs of bases depends only on the two parameters, T0 and Tc (critical temperature).
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560110105
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 32
    Electronic Resource
    Electronic Resource
    Quantum mechanical tunneling in synaptic and ephaptic transmission (1977)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 11 (1977), S. 103-127 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Quantum mechanical tunneling theory is applied to the problem of synaptic vesicle release and to the problem of electric transmission at the ephaptic junction. In the synapse the tunneling produces conformational changes in macromolecules to open and close vesicle macrogates. Quantum mechanical tunneling as a basis for charge transfer and physical release of vesicles at junction membranes provides a unified concept of ephaptic and synaptic transmission. Details of this model are in agreement with experimental data for miniature endplate potential frequency and delay effects as a function of polarization, osmotic pressure, and temperature. The theory accounts for anatomical specializations at the synaptic cleft and the narrow junction observed for the ephapse.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560110109
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 33
    Electronic Resource
    Electronic Resource
    Announcements (1977)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 11 (1977), S. 187-187 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560110117
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 34
    Electronic Resource
    Electronic Resource
    Theory of orientation and stereoselection. Author: Kenichi Fukui. Published by: Springer-Verlag, Berlin-Heidelberg-New York, 1975. Price: $18.10. No. of pages: 134 (1977)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 11 (1977), S. 185-185 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560110116
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 35
    Electronic Resource
    Electronic Resource
    Simplified methods for ab initio calculations. The valence states of CH2 and CH2+ (1977)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 12 (1977), S. 115-131 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Three simplifying methodds are discussed and applied to the four lowest valence states of CH2(3B1, 1A1, 1B1 and 1Σg+(1A1*)) and to the two lowest of CH2+(2A1 and 2∏u(2B1)). These methods concern: (1) the development of polarization functions for Gaussian-lobe basis sets by least-square fitting of numebrical multiconfigurational atomic fuinctions (this approach is tested also on (C2H2, (2) the use of intermediate Hamiltonians to calculate avoided crossings between potential hypersurfaces, and (3) thecalculation of correlation energies using an atoms-in-molecule approach.The calculated equilibrium geometries of the CH2 States are within 0.02 Å and 5° of available experimental data. The calculated term values and ionization potentials, Te(1A1 = 0.35 eV, Te (1B1) = 1.22 eV, Te (1Σg+(1A1*)) 2.48 eV, I.P. (2A1) = 10.39 eV and I. P. (2∏u(2B1)) = 10.58 eV, are in agreement with some recent theoretical studies, and are very close to existing experimental information.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560120111
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 36
    Electronic Resource
    Electronic Resource
    A note on the importance of d orbitals in the calculation of effective interactions and the excitation spectra of atoms and molecules (1977)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 12 (1977), S. 193-205 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The focal point of our discussion is the examination of truncated basis sets used in obtaining an accurate first principles clculation of the effective valence shell Hamiltonian by the canonical transformation-cluster expansion approasch. Subsequent diagonalization of this effecitve valence shell hamiltonian yields the valence shell transition energies. A detailed analysis of numerical results obtained using a number of different basis sets of hydrogen-like orbitals together with rigorous symmetry arguments celarly demonstrates the special role played by d orbitals in computing the 3P → 1D transition energy in carbon. The failure of early attempts to calculate the effective Hamiltonian for ethylene from first principles is examined in the light of recent ab initio calculations on ethylene involving d orbitals and the computations reported in this paper. We conclude that accurate calculations of the effective valence shell Hamiltonian for molecules must consider d orbitals in the excited orbital basis set.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560120115
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 37
    Electronic Resource
    Electronic Resource
    Quantum chemical calculations on thioridazinePresented at the International Symposium on Quantum Biology and Quantum Pharmacology, Sanibel Island, Florida, January 1975. (1976)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 10 (1976), S. 559-567 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Quantum chemical CNDO/2 calculations for the conformational preference of the side chain of thioridazine as a function of angle indicated the crystallographically determined structure gave the lowest energy. There is also a small region of conformational flexibility within the first 90° of rotation of the side chain. This is commensurate with the results which we had obtained previously for our similar calculations for promazine and its Cl and CF3 derivatives, perazine and its Cl and CF3 derivatives, and for the hypothetical hitherto unknown N-piperidinopromazine and its Cl and CF3 derivatives. The conformational profile of thioridazine resembles that of the perazines. The calculated gross atomic populations on the alkyl nitrogen in thioridazine was within the range we had previously found necessary for neuroleptic activity.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560100402
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 38
    Electronic Resource
    Electronic Resource
    Calculation of j and jm symbols for arbitrary compact groups. III. Application to SO3 ⊃ T ⊃ C3 ⊃ C1 (1976)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 10 (1976), S. 615-628 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The methodology developed in earlier papers is used to compute the 6j symbols and 3jm factors that arise in the group chain SO3 ⊃ T ⊃ C1. The relevant character theory is given and the 2j and 3j symbols calculated. Selection rules are used to predict which j symbols or jm factors are necessarily zero, and then a set of 6j fundamentals computed for T. The complete set of primitive 6j symbols are then computed by application of the orthogonality and Racah backcoupling relations. Primitive 3jm factors are calculated for SO3 ⊃ T and T ⊃ C3 and, from these, all the 3jm factors for T ⊃ C3 and some of those for SO3 ⊃ T computed. A complete table of non-equivalent 6j symbols for T and 3jm factors for T ⊃ C3 is given, together with a table for SO3 ⊃ T of all 3jm factors with j ≤ 2.
    Additional Material: 8 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560100406
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 39
    Electronic Resource
    Electronic Resource
    An interative scheme for electronic systems using one-electron green's functions (1976)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 10 (1976), S. 669-681 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: In this paper an iterative generalization of the minimum principle proposed for electronic systems by Hall, Hyslop, and Rees is investigated. It is shown that this generalization still retains the advantage of using members of a larger class of trial wave-functions, for example those with discontinuities, as initial approximations to the wave-functions. This scheme has the advantage that, at each stage of iteration, an upper bound is obtained which is at least as good as that obtained previously.The theory is first applied to the hydrogen atom. It is then adapted to estimate the Hartree-Fock energy of the helium atom, the Hartree-Fock limit being obtained after a relatively small number of iterations.
    Additional Material: 3 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560100410
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 40
    Electronic Resource
    Electronic Resource
    A characterization of pairs of subspaces for quantum chemical applications of the Galerkin-Petrov method (1976)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 10 (1976), S. 683-697 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A method is proposed for characterizing pairs of finite dimensional subspaces of the Hilbert space. The method might be helpful for the proper selection of coordinate and projective spaces leading to reliable realizations of the Galerkin-Petrov method for use in quantum chemistry. In order to illustrate the method some numerical results are presented.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560100411
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 41
    Electronic Resource
    Electronic Resource
    Masthead (1976)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 10 (1976) 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560100501
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 42
    Electronic Resource
    Electronic Resource
    Semi-quantitative and semi-empirical versions in the quasi-relativistic SCF-MO-LCAO methods: Numerical calculations for (PtCl6)2- (1977)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 11 (1977), S. 543-559 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Quasi-relativistic (QR) versions of the CNDO and Mulliken-Wolfsberg-Helmholz (MWH) semiempirical methods based on the SCF-QR-MO-LCAO method given earlier are worked out. For the CNDO method only the basic formulas and matrix element expressions are given, while for the MWH one, the parametrization as well as the basis functions and group spinor overlap integral calculation were discussed. (PtCl6)2- complex was chosen for a test calculation. The energy level values and LCAO coefficients were obtained and compared with the nonrelativistic calculations. One of the results was the occurrence of a very strong reduction of the spin-orbit interaction due to covalency. The calculation proves the semi-empirical versions of the QR-MO-LCAO method to be quite realizable in practice.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560110403
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 43
    Electronic Resource
    Electronic Resource
    Atomic SCF loge localized wave functionsPresented at the Second International Congress in Quantum Chemistry, new Orleans, Louisiana, U.S.A., April 1976. (1977)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 11 (1977), S. 715-723 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: We report in this work SCF atomic calculations for Li, Be, B, C, and Ne using a basis set of completely loge-localized functions. For these second row atoms the total volume R3 was partitioned into a spherical loge of radius R and its volume complement. The loge-localized basis functions were constructed as a product of Slater-type orbitals and a cut-off factor. The energy values obtained differ significantly from the Hartree-Fock ones indicating that the delocalization effects - not included in these calculations - are important.
    Additional Material: 6 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560110503
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 44
    Electronic Resource
    Electronic Resource
    The electronic structure and properties of pyrazine, its cation, and anion (1977)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 11 (1977), S. 767-773 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Gaussian orbital LCAO MO calculations are reported for pyrazine in its ground and first excited triplet state, together with calculations on its anion and cation. Energies, population analysis indices, and one-electron properties are compared across the series in order to investigate the differences in electron distribution.
    Additional Material: 5 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560110509
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 45
    Electronic Resource
    Electronic Resource
    A weakly bound, quantum-mechanical buridan's ass (1977)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 12 (1977), S. 759-763 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The spherical limit of a single particle in the field of three nuclei is shown to exhibit a variety of phenomena associated with the stability of the various extrema involved. Some consequences with respect to the general problem of detecting broken symmetry solutions of variational problems are pointed out.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560120412
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 46
    Electronic Resource
    Electronic Resource
    Third-order many-body perturbation theory for the ground state of the carbon monoxide molecule (1977)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 12 (1977), S. 737-757 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Many-body perturbation calculations have been performed for the ground state of the carbon monoxide molecule at its equilibrium internuclear separation. The calculations are complete through third order within the algebraic approximation; i.e., the state functions are parameterized by expansion in a finite basis set. All two-, three-, and four-body terms are rigorously determined, and many-body effects are found to be very important. A detailed comparison is made with a previously reported configuration interaction study. Padé approximants to the energy expansion are constructed. The many-body perturbative wave function is used in the Rayleigh quotient to produce upper bounds to the electronic energy.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560120411
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 47
    Electronic Resource
    Electronic Resource
    On convergence in many-shell SCF theory (1977)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 12 (1977), S. 765-776 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The effect of damping factors on convergence to general stationary solutions in many-shell SCF theory is discussed using a first order perturbation analysis. Their bearing on the maximum overlap criterion is examined and a comparison made with Hartree damping. Examples are drawn from numerical experience with hole state and transition operator calculations, some of which lead to saddle point stationary conditions. The method of Hsu et al. is reviewed in the light of the foregoing arguments.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560120413
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 48
    Electronic Resource
    Electronic Resource
    On the dependence of the energy given by a CI limited to double substitutions with respect to the number of electrons (1977)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 12 (1977), S. 777-779 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560120414
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 49
    Electronic Resource
    Electronic Resource
    PCILO calculations on hydrogen bonded complexes. Dimers involving second row atoms (1977)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 12 (1977), S. 805-811 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The PCILO method was used to study systems with the following types of intermolecular hydrogen bonds, involving 2nd row atoms: N…H—S, S…H—S, N…H—Cl, Cl…H—F, Cl…H—Cl, P…H—N, P…H—P, P…H—F, S…H—F.In all the cases calculated, the PCILO method yields an accurate qualitative description of the stabilization energies and to some extent quantitatively good agreement with reliable ab initio and experimental results. The corresponding equilibrium distances are in almost all cases smaller (up to 0.6 Å) than the ab initio values of the same compounds.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560120504
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 50
    Electronic Resource
    Electronic Resource
    PCILO calculations on hydrogen bonded complexes (1977)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 12 (1977), S. 841-850 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The PCILO method was used to study systematically systems with the following types of intermolecular hydrogen bonds: . In all cases the PCILO method gives a correct description of the stabilization energies in a good agreement with reliable ab initio results. The PCILO calculated equilibrium distances are only somewhat smaller than the corresponding experimental or ab initio values. Qualitatively, also, the changes in the charge distributions are in accordance with the results of ab initio calculations.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560120507
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 51
    Electronic Resource
    Electronic Resource
    Electron momentum distributions from valence-bond wave functions (1977)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 12 (1977), S. 105-113 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Momentum densities obtained from the Heitler-London (HL) wave functions for diatomic molecules and those from the corresponding valence-bond (VB) wave functions including ionic terms are compared. In each case they shown maxima in the direction perpendicular to the bond. However, the dependence of momentum densities on mutual orientations of the two electronic momenta is quite complex in the latter case. The improvement in the Compton profile on including the ionic terms is illustrated with the example of H2. The momentum denmsities obtained from the VB wave function constructed from orthogonalized atomic orbitals (OAO) have also been examined. The HL wave function with OAOS leads to the same momentum distribution as the repulsive state HL wave function constructed from overlapping AOS.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560120110
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 52
    Electronic Resource
    Electronic Resource
    The symmetric groups and the Waller-Hartree spin-free method (1977)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 11 (1977), S. 393-398 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The relations between the Waller-Hartree spin-free method and the symmetric group theory are given. It is shown that the Gallup method is a special case of ours with S = M. Furthermore, all the irreducible representation matrices and other matrices needed are written explicitly in terms of Sanibel coefficients which makes the method more useful. However, it was shown that the cases with S ≠ M for the spin-free pure spin states might be beyond the power of the symmetric group theory.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560110303
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 53
    Electronic Resource
    Electronic Resource
    Etude Quantique du Pouvoir Rotatoire Naturel et de la Biréfringence Gyrotropique dans un Cristal (1977)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 11 (1977), S. 381-391 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A quantum calculation of the optical activity and gyrotropic birefringence is used in a molecular crystal to deduce symmetry properties. A study of the variation of the components of these tensors, when a change of origin occurs, is used to account for the formula for the electric excitation proposed by Landau and Lifchitz. It is shown that the results obtained are valid in the case of crystals with nonlocalized electrons.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560110302
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 54
    Electronic Resource
    Electronic Resource
    Collision theory treatment of monomolecular and bimolecular gas reactions (1977)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 12 (1977), S. 495-503 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: An exact collision theory of unimolecular and bimolecular gas phase reactions is derived from a general quantum-mechanical formulation of reactions rates based on the assumption that the reactants are in thermal equilibrium. In this way the quantum corrections to the classical collision theory expressions are rigorously defined. Approximate formulas for these corrections make it possible to determine well the temperature ranges within which the classical and the semiclassical approximations are valid. A comparison is made between the collision and the transition state theory with emphasis on some conceptual difficulties of the latter in treating the simple decomposition and recombination reactions. It is shown that in the classical (high temperature) limit these theories are incompatible except when the reaction coordinate is entirely separable (i.e., when the transition state theory is no longer useful).
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560120308
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 55
    Electronic Resource
    Electronic Resource
    A semi-empirical MO theory for ionization potentials and electron affinities. II. Vertical and adiabatic values, benzenoid and nonbenzenoid aromatic hydrocarbons, and conjugated molecules with heteroatoms (1977)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 12 (1977), S. 527-544 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Further developments of a recent semiempirical, variable effective charge MO theory for calculation of ionization potentials (IP) and electron affinities (EA) as energy differences between separately minimized ground and ionized states are reported. The method is extended to adiabatic as well as vertical IPS and EAS by including core repulsion and σ bond compression energies in the total energy. The method is generalized to heteroatomic systems and is simplified by neglecting penetration integrals. As before, only two molecular parameters, the vertical IPS of benzene and naphthalene, are required to set the magnitude of the σ changes associated with the polarization of the core during loss or gain of a π charge. Twenty-seven aromatic molecules are studied, including polyacenes, condensed ring compounds, nonbenzenoids with five and seven member rings, nonplanar molecules, and heteroatomics with N+, as in pyridine, N+2, as in pyrrole, and O+2, as in furan. The results are within 0.2 eV of the photoelectron spectroscopic vertical IPS and the predicted vertical-adiabatic separation is consistent with the shape of the first band. The calculated EAS are within 0.2 eV of the observed values.The calculation is used to predict the IP and EA of the ionic photosensitizing cyanine dye, pinacyanol. The values obtained are consistent with the latest measured IP and EA of the adsorbed dye, corrected for surface and aggregation polarization effects.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560120311
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 56
    Electronic Resource
    Electronic Resource
    Relationship between orthogonalization and orbital localization proceduresPresented at the International Symposium of Dalseter (September 2-4, 1976) in honor of the 60th birthday of Prof. P.O. löwdin. (1977)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 12 (1977), S. 579-590 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A condition for the equivalence of the Löwdin orthogonalization method and various localization methods is derived, taking the matrix elements of the localizing operator into consideration. In the example of the π atomic orbitals of benzene, it is shown that the “ultralocalized” functions defined in the Anderson fashion with help of the Boys minimum-fluctuation criterion do not fulfill this condition, in contrast with a Ruedenberg-type localization.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560120316
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 57
    Electronic Resource
    Electronic Resource
    Masthead (1977)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 12 (1977) 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560120401
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 58
    Electronic Resource
    Electronic Resource
    Conformational energy map for a pair of peptide units using the bond polarisability method (1977)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 12 (1977), S. 671-681 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A method recently developed for the calculation of intramolecular nonbonded interactions based on experimental bond polarisabilities and atomic charges and transition π-charges obtained from MO calculations has been applied to the alanyl dipeptide. The potential energy contours in the φ, ψ plane obtained by this method compare favourably with those derived from the frequency of occurrence of conformations in globular proteins. An analysis of the various components of the nonbonded interaction energy indicates that the fairly frequent occurrence of conformations around φ = -80°, ψ=0° is presumably due to a favourable interaction of the π-polarisation.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560120407
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 59
    Electronic Resource
    Electronic Resource
    Optimum scaling in a Monte Carlo method for quantum chemistry (1978)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 13 (1978), S. 455-456 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560130315
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 60
    Electronic Resource
    Electronic Resource
    Thermodynamics of the DNA helix-coil transition (1978)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 13 (1978), S. 499-507 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The thermodynamics of the DNA helix-coil transition is studied, starting from the thermodynamical potential difference between the states helix and coil; this potential difference is understood as the difference in free energies. With only three parameters obtained from experimental data different quantities of the T2 phage DNA molecule are calculated. It is observed that the phase transition is of second order.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560130405
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 61
    Electronic Resource
    Electronic Resource
    Notes on density matrix model for coherent x-ray diffraction (1978)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 13 (1978), S. 801-810 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: It is shown how an idempotent density matrix provides a proper model for interpretation of the x-ray coherent diffraction experiment.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560130611
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 62
    Electronic Resource
    Electronic Resource
    Electronic structure of SiH2, PH2, and their positive and negative ions (1978)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 14 (1978), S. 39-53 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Ab initio LCAO-MO-SCF calculations on SiH2 and PH2 and their positive and negative ions are reported, using a variety of Gaussian basis sets. The charge distribution, bonding, and molecular properties of these ions are compared with the available experimental data.
    Additional Material: 7 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560140105
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 63
    Electronic Resource
    Electronic Resource
    Maximum and minimum overlap, localized, and hybrid orbitals for atoms and molecules by means of orthonormality-constrained variation (1978)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 13 (1978), S. 199-206 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: It is shown that application of the orthonormality-constrained variation method to the absolute squares of three kinds of overlap integrals leads to eigenvalue equations and of which the eigenvectors belonging to maximum (minimum) eigenvalues are the maximum (minimum) overlap, localized, and hybrid orbitals. In the eigenvalue equations, coupling operators similar to those used in SCF theory are found to occur. Connection of the maximum orbitals to a many-shell model, a simple MO theory, and Löwdin's orthonormalization is also discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560130205
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 64
    Electronic Resource
    Electronic Resource
    CNDO calculation of polarizabilities including polarization functions in the basis set (1978)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 13 (1978), S. 235-238 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Electric polarizabilities are calculated by solving the first- and second-order perturbation equations through a variational procedure. Satisfactory numerical results are obtained for a number of molecules using the CNDO approximation with an extended basis set.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560130209
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 65
    Electronic Resource
    Electronic Resource
    Principles of Ultraviolet Photoelectron Spectroscopy. J. W. Rabalais. Wiley-Interscience Monographs in Chemical Physics, New York, 1977. Price: $22.50. (1978)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 13 (1978), S. 263-263 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560130213
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 66
    Electronic Resource
    Electronic Resource
    Angular dependence of Gaussian-Lobe orbitals. II. Set of axial Gaussian-Lobe orbitals (1978)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 13 (1978), S. 311-324 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The topological properties of real spherical harmonic representations on the unit sphere have been found to provide a convenient tool to infer the lobe edifices which mimic these orbitals. The prohibitive number of lobes required in such an approach for l 〉 2, can be avoided in using only axial Gaussian-lobe orbitals (AGLO). It is proved that 2l + 1 independent Ylo-like functions correctly span the relevant Ylm (m = -l,l) subspace. The multipolar component analysis of any spatial arrangement of lobes is derived, and allows the optimization of the angular dependence of AGLOS. The cases of d- and f-orbitals are studied in detail and accurate optimized functions are proposed. This method can be easily extended to obtain the atomic orbitals of any azimuthal quantum number l-subspace.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560130305
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 67
    Electronic Resource
    Electronic Resource
    A comparative study of multiple scattering calculations on CrF63- (1978)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 13 (1978), S. 367-374 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The multiple scattering molecular orbital method, with different choices of sphere radii and local exchange, is applied to the cluster CrF63-. The orbital energies are almost always in the same order but uniformly moved up or down the energy scale depending on which parameters are used. Charge densities are only slightly dependent on the parameters. A method to avoid interaction with Rydberg-like states is suggested.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560130309
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 68
    Electronic Resource
    Electronic Resource
    Perturbation corrections to Koopmans' theorem. IV. Energy-shifted perturbation theory (1977)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 12 (1977), S. 549-559 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Energy-shifted perturbation theory is studied in connection with corrections to Koopmans' theorem. The first three vertical Ionization potentials of N2, C2H2, and HCN are computed with basis sets of double-zeta Gaussian-type orbitals and double-zeta GTO plus polarization functions. The average absolute deviation of calculation ionization potentials from the observed values is found to be 0.4 eV, whether one uses Brillouin-Wigner or Rayleigh-Schrödinger perturbation theory.
    Additional Material: 6 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560120313
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 69
    Electronic Resource
    Electronic Resource
    Announcements (1977)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 12 (1977), S. 591-591 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560120317
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 70
    Electronic Resource
    Electronic Resource
    Diagrammatic perturbation theory: Potential curves for the ground state of the carbon monoxide molecule (1977)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 12 (1977), S. 609-622 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Diagrammatic many-body perturbation theory is used to calculate the potential energy function for the X1 σ+ state of the CO molecule near the equilibrium nuclear configuration. Spectroscopic constants are derived from a number of curves which are obtained from calculations taken through third order in the energy. By forming [2/1] Padé approximants to the constants we obtain: re = 1.125 Å (1.128 Å), Be = 1.943 cm-1 (1.9312 cm-1), aBe = 0.0156 cm-1 (0.0175 cm-1), We = 2247 cm-1 (2170 cm-1), WeXe = 12.16 cm-1 (13.29 cm-1), where the experimental values are given in parenthesis.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560120403
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 71
    Electronic Resource
    Electronic Resource
    Orthogonal trajectories of the electron density (1977)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 12 (1977), S. 623-637 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Functions of several variables, such as the electron density and the nuclear Born-Oppenheimer potential, may be analysed very effectively using orthogonal trajectories. In particular the behaviour of these trajectories at critical points of the functions is investigated in detail. The use of orthogonal trajectories in the virial partitioning of Bader and in the definition of reaction coordinates is extended. A chemical interpretation of the critical points is suggested. The relevance of catastrophe theory is illustrated.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560120404
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 72
    Electronic Resource
    Electronic Resource
    Simplifications in the generation and transformation of two-electron integrals in molecular calculations (1977)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 12 (1977), S. 683-705 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Approximate numerical linear dependence among the columns of the two-electron integral matrix and the positiveness of the Coulomb operator are exploited in order to reduce the number of integrals that need to be calculated when a numerical accuracy is given by the machine in use or by the choice of the investigator. Numerical results presented indicate that the method leads to an algorithm for carrying out the two-electron integral four-index transformation which in practice can be achieved in a small fraction (˜1/5-1/3) of the time required to generate the integrals by one of the fastest available Gaussian integral programs, Almlöf's MOLECULE. This effectively removes one of the major bottlenecks of computational quantum chemistry.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560120408
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 73
    Electronic Resource
    Electronic Resource
    The physics of the born-oppenheimer approximation (1977)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 12 (1977), S. 721-735 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A new derivation of the Born-Oppenheimer separation of electronic and nuclear motion is presented. The arguments used differ from those in earlier works in not being specially designed for molecules. Instead they aim at an intuitive understanding of the qualitative behavior of the low energy bound states of any, real or hypothetical, Coulomb interacting system of particles. The virial theorem is the starting point of the discussion. After a brief explanation of how it can be used to understand atomic structure it is applied to molecules. It is found that coordinates of collective and individual motion are natural coordinates for the approximate separation, rather than nuclear and electronic. It is also shown that it is the form of the interaction between the particles that is responsible for the separation; the smallness of met/MNu is irrelevant.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560120410
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 74
    Electronic Resource
    Electronic Resource
    Hermitian form of the secular equation in the complex molecular orbitals method (1977)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 12 (1977), S. 781-783 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560120415
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 75
    Electronic Resource
    Electronic Resource
    On some specific properties of systems endowed with dipole-dipole interactions (1977)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 12 (1977), S. 785-794 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Specific properties of systems with dipole-dipole interactions in the one-dimensional structures leading to the violation of the statistical equivalent of the continuity equation resulting in the creation of qualitatively new excitations are analyzed. Those excitations are the result of the interaction between the initial quasiparticle currents. The structures discussed may be of importance in biophysics, and the biophysical aspects of the obtained results are considered. In comparison with other mechanisms, the exciton mechanism is shown to be of a very specific nature as its transport properties are sharply dependent upon the type of exciting light bounded within the range of temperatures covered by living organisms. This can result in an accumulation of interface excitations on a specific lattice molecule and cause its qualitative transformations with corresponding biological consequences.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560120502
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 76
    Electronic Resource
    Electronic Resource
    Calculation of molecular crystals within the PCILOCC framework (1977)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 12 (1977), S. 851-858 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Stabilization energies and equilibrium distances of one-dimensional (HF)n and (H2O)n chains have been calculated by means of the PCILO method for finite chain length and by the PCILOCC method for infinite chain length. Both types of calculation are compared with corresponding CNDO/2-MO and CNDO/2-CO calculations. Further we have performed an analysis of the individual contributions of the stabilization energies per monomer of the PCILO and PCILOCC calculations.The results show that the PCILOCC method is well suited for the calculation of molecular associations with translational symmetry.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560120508
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 77
    Electronic Resource
    Electronic Resource
    Electronic absorption spectra of V2O5 (1977)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 12 (1977), S. 915-923 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: MO calculations of electronic structure and optical transitions for [VOn]5 -; 2n (n = 4, 5, 6) clusters in V2O5 monocrystals have been carried out by means of the semiempirical CNDO CI method. Using the calculated results, a complete analysis of V2O5 optical data as available in the literature and as obtained in the electroreflectivity experiments presented in this paper is performed. An identification of optical transitions in a wide energy range is presented. The optical properties of vanadium pentoxide are shown to be due to the localized charge transfer electronic transitions in the clusters. The fine structure of optical spectra is connected with the covalent splittings of the vanadium 3d and oxygen 2p atomic levels.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560120512
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 78
    Electronic Resource
    Electronic Resource
    Breit-type three-electron equation in the Pauli approximation (1977)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 12 (1977), S. 925-935 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: We have reduced the Breit-type equation written down for 3 electrons to the 8 large components of the wave function in the (v/c)2 (Pauli) approximation. This procedure required appropriate handling of the 64 scalar equations which result in this instance. According to the results obtained within the accuracy of (v/c)2 all the terms are the same as those obtained by summing up the terms of the reduced 2-electron Breit's equation to 3 electrons. This statement is no longer valid, however, if during the reduction procedure we would go beyond the (v/c)2 approximation. Finally there is a discussion about how to begin developing a relativistic many-electron theory valid for the inner shell electrons of heavy atoms within the accuracy of the fine structure constant.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560120513
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 79
    Electronic Resource
    Electronic Resource
    Masthead (1977)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 12 (1977) 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560120601
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 80
    Electronic Resource
    Electronic Resource
    Molecular calculations with the MODPOT, VRDDO, and MODPOT/VRDDO procedures. IV. Boron hydrides and carboranesPresented at the International Symposium on Quantum Chemistry and Solid State Physics, Sanibel Island, Florida, January 1977. (1977)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 12 (1977), S. 937-961 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Reference completely ab initio 6-3G and nonempirical 3G/MODPOT (ab initio effective core model potential) LCAO-MO-SCF calculations (using the same valence atomic orbital basis) were performed for a series of boron hydrides (B4H10, B5H9, B5H11, and B6H10) and a test 3G/MODPOT + VRDDO (variable retention of diatomic differential overlap for charge conserving integral prescreening) calculation were also performed for B5H9, B6H10, and B10H14. The agreement between the ab initio 6-3G and the corresponding 3G/MODPOT calculations was excellent for valence orbital energies, gross atomic populations, and dipole moments. The results also compared favorably to previous ab initio minimum STO basis results of Lipscomb and coworkers. The 3G/MODPOT + VRDDO calculations verified that for such spatially compact molecules (such as boron hydrides, which are fragments of polyhedra), the VRDDO procedure does not result in a noticeable savings in computer time for molecules of the size and shape of B5H9 and B6H10, in contrast to the savings previously realized for organic molecules of comparable atomic size. However, the agreement in calculational results between the 3G/MODPOT and the 3G/MODPOT+VRDDO results was still as extremely close as it had been for the organic molecules.3G/MODPOT calculations were also carried out for B8H12, B9H15, B10H14, B10H14-2, 1,2-C2B4H6, and 1,6-C2B4H6 and the results compared to the previous minimum STO basis results. For B10H14, the 3G/MODPOT+VRDDO method led to savings in computer time of 28% over the 3G/MODPOT method itself.The agreement of the 3G/MODPOT results with available experimental photoelectron spectral data for B5H9 and 1,6-C2B4H6 was as good as that of the previous ab initio minimum STO basis calculations.
    Additional Material: 12 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560120514
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 81
    Electronic Resource
    Electronic Resource
    Complex scaling transformations in stationary and scattering problemsTalk presented at the 1978 Sanibel Symposium (Florida). (1978)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 14 (1978), S. 353-359 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: We review the methods and some applications of complex scaling transformation as well as some goals that now seem accessible using this technique in atomic and molecular physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560140404
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 82
    Electronic Resource
    Electronic Resource
    An application of the method of conjugate gradients to the calculation of minimal basis set localized orbitals (1978)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 13 (1978), S. 1-16 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Using an STO-3G basis set, energy localized molecular orbitals (LMO) were determined for the ten electron series HF, H2O, NH3, and CH4 as well as for CH3OH and C2H2F2. The method of conjugate gradients is shown to be a viable alternative to other non-eigenvalue methods. The characterization of the LMO in terms of first and second moment measures indicates that the STO-3G basis set LMO may be accurately correlated to larger sp basis set LMO. Also, it is shown that the first and second moment measures display a good linear correlation with the classical concept of electronegativity.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560130102
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 83
    Electronic Resource
    Electronic Resource
    The relationship between the unrestricted and projected Hartree-Fock methods in a simple three-electron model system (1978)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 13 (1978), S. 41-65 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Various forms of the unrestricted Hartree-Fock (UHF) scheme are studied for a simple three-electron model system, represented by the PPP (Pariser-Parr-Pople) π-electron model of the allyl radical. Both spin and space symmetry are violated in the UHF trial wave function, either individually or simultaneously. A comparison with the projected Hartree-Fock (PHF) schemes studied earlier is made and the effect of the order in which various symmetries are broken in both UHF and PHF schemes is studied. The effectiveness of various schemes follows from a comparison of the correlation energy and the wave function is obtained by various UHF (or projected UHF) and PHF schemes, in the whole range of the coupling constant, with the corresponding quantities given by the exact solution of the model. Finally, the implications of the stability of the restricted HF solutions for the behavior of various single- and multiparameter UHF and PHF schemes are briefly outlined and exemplified on the studied model.
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560130105
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 84
    Electronic Resource
    Electronic Resource
    Electronic absorption and emission spectra of nucleic acids and their components: Some questions of theory and experimentPresented at the International Conference on Quantum Chemistry, Biology, and Pharmacology held at Kiev, U.S.S.R., September 1978. (1980)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 17 (1980), S. 307-320 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The results of calculations of the transition energies and polarization in nucleotide bases performed by the CNDO/S CI method are compared with experimental data for long-wavelength and vacuumabsorption bands. The calculations and the analysis of experimental data testify to the existence of n - π* transitions in the first absorption bands of the bases. The study of double-stranded polynucleotides and DNA hypochromism based on the theoretical electronic characteristics of the bases and perturbation theory is performed. The role of stacking and complementary interactions within the hypochromic effect is cleared up. Two mechanisms for the shift of the fluorescence band maximum are investigated: two-proton transfer along H bonds and excimer formation. The study of H-bond potential curves shows the disadvantage of two-proton phototautomerism in the nucleotide base pairs in contrast to model systems. The possibility of excimer state formation in stacked homo- and heterodimers of nucleotide bases is shown within the extended-Hückel treatment. The nature of excimer minimum for the excited-state potential curve is analyzed.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560170214
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 85
    Electronic Resource
    Electronic Resource
    Masthead (1980)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 17 (1980) 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560170301
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 86
    Electronic Resource
    Electronic Resource
    Hydrophobic “pocket” on photosynthesizing membrane near photosystem IIPresented at the International Conference on Quantum Chemistry, Biology, and Pharmacology held at Kiev, U.S.S.R., September 1978. (1980)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 17 (1980), S. 361-366 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Studies concerning the effect of 2-alkyl pyridine N-oxides with different substituents on electron transfer, phosphorylation, and light-dependent proton transport in photosynthesizing membranes of chloroplasts were conducted. It is determined that 2-alkyl pyridine N-oxides with short alkyl chains stimulate the Hill reaction and light-dependent proton transport inside chloroplasts. Compounds having alkyl residues with 6-10 carbon atoms in the chain inhibit electron transport, ADP phosphorylation, and reduction of ferrocyanide in thylakoids. A conclusion is drawn on the presence of the hydrophobic “pocket,” which is of importance for organization of the electron-transport chain of chloroplasts, near photosystem II.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560170218
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 87
    Electronic Resource
    Electronic Resource
    Interactions and self-organization of nucleic bases, nucleotides, and polynucleotides into ordered structures. Effect of ionization and solvent salt compositionPresented at the International Conference on Quantum Chemistry, Biology, and Pharmacology held at Kiev, U.S.S.R., September 1978. (1980)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 17 (1980), S. 339-359 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: This paper summarizes our findings on the effects of protons and neutral salt ions on intermolecular interactions and the self-organization of nucleotide systems in aqueous media, both at monomer and polymer levels. To gain quantitative information about these processes, methods were developed to determine the thermodynamic parameters of monomer association from the data obtained by various experimental techniques (NMR, UV spectroscopy, and spin labeling) and to estimate the individual contributions of base stacking and H-bonding in ordered structures of polynucleotides and their complexes. The main results obtained using these methods are as follows. (i) A difference was discovered in the effects of positive and negative charges on the stacking interaction between ionized and neutral molecules of nucleic heterocycles. Protonation strongly decreases the heterocycle ability to form ordered stacks whereas deprotonation slightly affects stacking. (ii) Base-phosphate interaction, which has not yet really been investigated, was studied. This interaction, along with base stacking, governs nucleotide association in water media. It appears upon protonation of the base moiety and increases with decreasing ionic strength. (iii) Base stacking was found to become stronger under the action of salt anions stabilizing the water structure and it became weaker under the action of destabilizing salt anions, both in monomer and polymer systems, which is indicative of an indirect mechanism of the anionic effects. It is essential that small salt ion additives acting by such a “distance” mechanism can affect the formation of ordered structures in nucleotide systems as strong as the direct interaction of the bases with protons. (iv) The results obtained suggest that an increase in solvent entropy upon the self-organization of nucleotide systems in aqueous media may be an important factor promoting these processes. (v) As follows from our data, specific weakening or strengthening of intermolecular interactions by protons and salt ions at small, physiological-range changes in pH or solvent salt composition seems to be an effective regulatory mechanism for the functioning of nucleotide systems.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560170217
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 88
    Electronic Resource
    Electronic Resource
    On the validity range of the qualitative theory of chemical reactivity (1980)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 17 (1980), S. 399-413 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: An attempt is made to refine the physical background underlying qualitative quantum-chemical concepts that are an essential component of the modern theory of chemical reactivity. The energy of electron delocalization in a transition state (stabilization energy, SE) is used as a measure of chemical reactivity. Using Coulson's integral representation for bond order matrix enables one to present the Woodward-Hoffmann rules and the effects of conjugated substitutents as theorems for a Hückel SE in alternant systems. A part of the results are extended to heteroatomic systems. The validity of the present treatment is discussed in terms of the SCF PPP theory.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560170303
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 89
    Electronic Resource
    Electronic Resource
    Fock coordinate function method for separation of spin variables in transition density matrices (1980)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 17 (1980), S. 415-428 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The Fock generating function method is employed for the separation of spin variables into two-particle transition density matrices. Their spatial components introduced by McWeeny are expressed through Schrödinger's coordinate wave functions. Some nontrivial integral relations between these components and the charge and transition spin density matrices are obtained. The interrelation between the mentioned spatial components and the Matsen-Poshusta symmetrized density matrices of an arbitrary spatial function is found.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560170304
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 90
    Electronic Resource
    Electronic Resource
    Polarization effects in photosynthetic membranesPresented at the International Conference on Quantum Chemistry, Biology, and Pharmacology, held at the Institute for Theoretical Physics, Kiev, U.S.S.R., 18-22 September 1978. (1980)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 17 (1980), S. 587-593 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: This paper investigates the polarization effects associated with functional processes in photosynthetic membranes.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560170315
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 91
    Electronic Resource
    Electronic Resource
    Calculation of molecular electric polarizabilities and dipole moments. III. BH moleculeResearch was supported by the National Science Foundation under Grant No. CHE 77-22638. (1980)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 17 (1980), S. 479-483 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: We use a previously proposed variation-perturbation method to calculate the electric polarizabilities and the electric dipole moment at equilibrium nuclear distance of the BH molecule. We obtain 3.56 × 10-24 cm3 for the perpendicular polarizability αxx and 3.22 × 10-24 cm3 for the parallel polarizability αzz. Our result for the electric dipole moment μ0 is 1.734 debye units; there is no reliable experimental result to compare it with.
    Additional Material: 3 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560170309
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 92
    Electronic Resource
    Electronic Resource
    A direct CI method with a multiconfigurational reference state (1980)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 17 (1980), S. 485-500 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A method for direct configuration-interaction (CI) calculations with a multiconfigurational reference function is described. The reference state can contain several closed-shell electronic configurations and the CI expansion comprises all single and double replacements out of all these configurations. The resulting secular problem is solved using a variation-perturbation method. A number of examples are given showing the efficiency of the method. The largest CI expansion used in calculations with this program so far contains 76,471 spin- and space-symmetrized configurations.
    Additional Material: 4 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560170310
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 93
    Electronic Resource
    Electronic Resource
    Accurate and stable numerical Hartree-Fock calculations for atoms. I. The 1s2 ground state of H-, He, Li+, and Be++ (1979)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 15 (1979), S. 449-462 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: New techniques have been developed for atomic self-consistent-field calculations by numerical integration. For the origin and tail regions we present analytical expansions which can represent the solutions to high accuracy. For the numerical integration in the central region a five-point generalization of the Numerov formula is used; the error term is of the order h10. While this formula is unstable if used in the customary way, stability is achieved by using a Gaussian elimination technique. The new procedures are tested on the ground state of the helium isoelectronic series; with 251 integration points all quantities are calculated with an inherent accuracy of better than 10-11.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560150502
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 94
    Electronic Resource
    Electronic Resource
    Correlation problems in atomic and molecular systems. VII. Application of the open-shell coupled-cluster approach to simple π-electron model systems (1979)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 15 (1979), S. 463-479 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The coupled-cluster variational-like direct approach to the calculation of ionization and electron attachment energies and of excitation energies is applied to several π-electron model systems, using the PPP Hamiltonian with various parametrizations. A simple approximation, which represents the triexcited clusters in terms of disconnected W1T2 terms, is employed. All the necessary diagrams for both excitation energy and ionization potential (electron affinity) calculations are given in the compact Hugenholtz nonoriented form. The results of the calculations for benzene, trans-butadiene, all-trans-hexatriene, and fulvene are compared with the corresponding full CI results, and the conclusions about the validity and efficiency of this approach are drawn.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560150503
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 95
    Electronic Resource
    Electronic Resource
    Role of Ca+2 ion in the abortifacient action of prostaglandins. I. Molecular-orbital and conformation-energy calculations of PGF2α (1979)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 15 (1979), S. 481-489 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The paper reports the study of a possible mechanism of Ca+2 activation of prostaglandin PGF2α on the basis of molecular-orbital and conformation-energy calculations. The electronic charges on various atoms of the molecule have been evaluated from the available crystallographic data by the extended Hückel theory (EHT). Conformation energies were calculated for intrinsic torsional rotations around the C11—C12, C7—C8, and C14—C15 bonds. The minimum energy conformation was found to differ from the crystallographic conformation by 9.3 kcal/mol. Some additional local energy minima are also reported within this range. The calculation of the long-range interchain interaction energy between the α and ω chains shows variation with conformation. The binding site for the Ca+2 ion has been estimated on the basis of the molecular electrostatic potentials. Such a binding site was found near the carboxyl group, which agrees with the current chemical thinking. Changes in the electronic charge distribution due to Ca+2 complexation were studied by EHT method using the supramolecular approach. Calcium complexation decreases the conformation energy by 2-3 kcal/mol and has a small effect on the interchain interaction energy.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560150504
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 96
    Electronic Resource
    Electronic Resource
    Nonbonded interactions in membrane-active cyclic biopolymers. III. Analogs of valinomycin (1979)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 15 (1979), S. 491-497 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Several analogs of valinomycin have been simulated. These are analogs obtained by changing the configuration of the amino acid and hydroxy acid residues one at a time. Nonbonded interactions have been calculated for three conformations of each analog. The electrostatic and polarization contributions to the energy are conformation selective, whereas the Pauli repulsion is the only component which is isomer selective. For the ring chirality considered here the analog of valinomycin having all the three L-valyl residues replaced by D-valyl residues is predicted to be frozen in a “top open” conformation.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560150505
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 97
    Electronic Resource
    Electronic Resource
    Ab initio study of a purine nucleoside: Adenosine (1979)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 15 (1979), S. 499-510 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The ab initio SCF LCAO-MO method is used to compute the main electronic properties of a purine nucleoside, adenosine, in two specific conformational arrangements (3′-endo conformation of the ribose, gt orientation of the extracyclic CH2OH group, anti orientation of the base with respect to the sugar and 3′-endo conformation of the ribose, gg orientation of the extra-cyclic CH2OH group, syn orientation of the base with respect to the sugar). The results are compared with those performed for the isolated component fragments, adenine and 3′-endo riboses.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560150506
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 98
    Electronic Resource
    Electronic Resource
    Variational principle for obtaining approximate analytical solutions of the temperature-perturbed Thomas-Fermi equation for compressed atoms (1980)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 17 (1980), S. 737-745 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A temperature correction to the Thomas-Fermi (TF) model of a neutral compressed atom has been given by Marshak and Bethe. The aim of the present work is to point out that, by formulating a variational principle, one may obtain approximate analytical solutions of the temperature-perturbed TF equation. As a test of the proposed theory, the total energy of a Ne atom, confined to a spherical container, has been calculated as a function of the container radius at T = 0°K. Comparison of the data obtained with energy values calculated by Ludeña, using a self-consistent-field Hartree-Fock approach, shows reasonable agreement. It is, therefore, concluded that the variational approach suggested in this paper is a sound one.
    Additional Material: 5 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560170414
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 99
    Electronic Resource
    Electronic Resource
    Atomic and molecular collision theory (1980)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 17 (1980), S. 1042-1042 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560170518
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 100
    Electronic Resource
    Electronic Resource
    Theoretical description of fluidity in biological membranes: Rotational motion in lipid hydrocarbon chains (1980)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 17 (1980), S. 983-993 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A mathematical model to relate order and rotational motion in lipid hydrocarbon chains in biological membranes is proposed. Schrödinger equations with suitable potential functions for C—C rotations in lipid hydrocarbons chains have been solved to obtain wave functions characterizing these motions. For a free chain a threefold potential function has been assumed. The effect of collisions between neighboring chains in a membrane is considered by including another term (δ function) in the potential function.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560170513
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...