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
  • 1
    Electronic Resource
    Electronic Resource
    Ab initio MO calculations for hexacyano complexes (1982)
    s.l. : American Chemical Society
    Inorganic chemistry 21 (1982), S. 3837-3841 
    Details
    ISSN: 1520-510X
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/ic00140a048
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Ab initio RHF and CASSCF studies on Fe–O bond in high-valent iron-oxo-porphyrins (1988)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 88 (1988), S. 303-312 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: The electronic structure of the Fe–O bond in highly oxidized iron porphyrins was elucidated by ab initio RHF (restricted Hartree–Fock) and CASSCF (complete active space SCF) calculations on a neutral complex FeP(py)O (P=porphine, py=pyridine), which is a model of peroxidase compound II. Accounting for the correlation effects is essential for the description of the Fe–O bond. Equilibrium distance and stretching frequency of Fe–O were calculated from the potential energy curves obtained by CASSCF. Furthermore, Mössbauer spectrum parameters (quadrupole splitting, isomer shift, asymmetry parameter and direction of the principal axis of the electric field gradient tensor) and spin density were evaluated. They are in good agreement with experiments on the whole. The oxidation number of iron in peroxidase compound II was assigned to IV through an analysis of the CASSCF wave function.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.454655
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Ab initio MO study on equilibrium bond distance between Fe and pyridine in bis(pyridine)(porphinato) iron for various electronic states (1985)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 82 (1985), S. 3716-3721 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: For bis(pyridine)(porphinato) iron [FeP(py)2], a correlation between the iron electronic state and the equilibrium Fe–Npy distance was investigated. Potential energy curves as a function of the Fe–Npy distance were calculated for low-spin, intermediate-spin, and high-spin states of the ferric and ferrous ions by the ab initio SCF MO method. The equilibrium Fe–Npy distances were obtained from the potential curves. The values obtained for the ferric low-spin and high-spin states were in good agreement with the experimental values for Fe(III)(OEP)(3-Clpy)2 within the differences, ±0.05 A(ring). The following significant features were found. The equilibrium distance is elongated by the occupation of the 3dz2 orbital and is shortened by the oxidation of the iron atom. The distance and the force constant for the symmetrical py–Fe–py stretching are strongly correlated with the overlap population between the 3dz2 orbital and pyridine–nitrogen orbitals.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.448907
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Ab initio MO study on relationships between the electronic state and out-of-plane displacement of the iron atom in four-coordinate Fe-porphine (1985)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 82 (1985), S. 848-855 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: The potential energy curves as a function of the out-of-plane displacement of the iron atom in Fe-porphine were calculated for various spin states and oxidation states of the iron atom by the ab initio SCF MO method. It was found that porphine attracts the iron atom to the center of the porphine plane for all the electronic states. The force constant for the out-of-plane motion of the iron atom is decreased by the occupation of the dx2−y2 orbital and increased by oxidation of the iron atom. It was also found that the force constant is strongly correlated with the overlap population between the dx2−y2 orbital and the pyrrole–nitrogen orbitals.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.448511
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Optical saturation and quenching effects in the triplet state of Rhodamine 6G at 77.deg.K (1974)
    s.l. : American Chemical Society
    The @journal of physical chemistry 〈Washington, DC〉 78 (1974), S. 2006-2009 
    Details
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/j100613a006
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Pure quadrupole resonance of iodine in tetraiodothallates(III) (1967)
    s.l. : American Chemical Society
    The @journal of physical chemistry 〈Washington, DC〉 71 (1967), S. 4443-4448 
    Details
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/j100872a043
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Theoretical study of equilibrium Co—F bond distance of CoF6n- complexes (n = 4, 3, and 2) in crystals (1983)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 24 (1983), S. 85-96 
    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 equilibrium Co—F bond distance and the a1g vibrational frequency of CoF6n- complexes (n = 4, 3, and 2) in crystals were investigated from a theoretical point of view. Ab initio SCF MO calculations were performed for the isolated CoF6n- complexes in order to obtain the potential energy curves against the Co—F distance. These potential energy curves were improved by considering the effect of the surrounding ions. It is shown that the effects of the next-nearest neighbors (eight K+ ions) and the next-next-nearest neighbors (six Co2+ ions) are very important in determining these properties for “ionic” KCoF3 crystal. On the other hand, for Cs2CoF6 crystal, in which the Co—F bond has considerable degree of covalency, the shape of the potential energy curve is almost completely determined by the nonelectrostatic component of the intramolecular interaction of the isolated CoF62- unit.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560240108
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Ab initio MO study of Fe out-of-plane displacement and Fe-ligand vibration in five-coordinate Fe-porphyrin (1987)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 32 (1987), S. 661-668 
    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 SCF MO calculations were carried out for fluoro(porphinato)iron(III) in order to elucidate the origin of the out-of-plane displacement of the iron atom and to analyze vibrational modes of the axial ligand bond. Potential curves as functions of the Fe out-of-plane displacement and Fe—F bond distance were calculated for the ground state. By using these potential curves, the equilibrium iron displacement, Fe—F bond distance, and normal mode frequency of the Fe—F stretching vibration were evaluated. The values are in good agreement with experimental values within the differences 0.02 Å, 0.06 Å, and 50 cm-1, respectively. It has been confirmed that the Fe out-of-plane displacement is caused mainly by the Coulomb repulsion between porphine nitrogens and fluorine anion.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560320765
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Test of an integral approximation scheme based on semiorthogonalized orbitals in LCAO SCF MO CI calculations of naphthalene (1977)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 12 (1977), S. 449-456 
    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
    Notes: Ab initio LCAO SCF MO CI calculations of naphthalene are carried out with a minimal basis set to test an integral approximation scheme proposed in a previous paper. When 71.3 and 53.0% of the two-electron integrals are neglected, the errors in the SCF total energy are only -0.0534 and -0.0006 a.u., respectively. In the latter case, the maximum absolute errors of the orbital energy and the gross AO population are 0.007 a.u. and 0.001, respectively. Even in the former case the errors of the excitation energies are less than 0.0004 a.u. Errors of oscillator strengths are also examined and are found to be tolerably small.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560120304
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Integral approximations on the basis of semiorthogonalized orbitals (1976)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 10 (1976), S. 135-141 
    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: Semiorthogonalized orbitals are introduced as a basis of approximate ab initio molecular calculations. The semiorthogonalized orbitals are obtained from the usual overlapping atomic orbitals by means of a generalized Löwdin transformation. The new orbitals are characterized by two features: many overlaps between them are zero, and they are close to their corresponding initial atomic orbitals. On the basis of the semiorthogonalized orbitals, a scheme of integral approximations is proposed which allows one to carry out approximate ab initio calculations with less computational efforts and thus offers a possibility to perform calculations on much bigger molecules with limited computational facilities. Results are presented for model calculations on the anthracene π-electron system. Orbital energies and electron distribution are quite close to the rigorously calculated values.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560100111
    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...