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
    A theoretical analysis of a diamond (100)-(2×1) dimer bond (1995)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 102 (1995), S. 5486-5491 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: The nature of the bonding between the carbon atoms of reconstructed dimers on a dehydrogenated (100)-(2×1) diamond surface is examined. Utilizing a complete active space self-consistent field (CASSCF) description and a 6-31G** basis set it is demonstrated that such dimer units form a biradical and are not purely π bonded as has often been conjectured. The significance of these findings for growth mechanisms on diamond surfaces involving radical sites is discussed. © 1995 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.469277
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Quantum calculations of the effect of bend excitation in methane on the HCl rotational distribution in the reaction CH4+Cl→CH3+HCl (2000)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 113 (2000), S. 4495-4497 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: We report novel, reduced dimensionality quantum calculations of the effect of bend excitation in methane on the rotational distribution of HCl in the reaction CH4+Cl→CH3+HCl. We use a modification of a semiempirical potential developed by Yu and Nyman in these calculations. Reaction probabilities for zero total angular momentum are obtained using an L2 wave packet method for selected HCl rotational states (in the ground vibrational state) and summed over final CH bend/stretch states in CH4. The calculations are done in two ranges of the total energy. In the low energy range only the ground bend/stretch state of CH4 is open, and in the higher energy range that state and the second excited bend state are energetically open. With just the ground state of CH4 open we find a cold, unimodal rotational distribution of HCl, in qualitative agreement with experiment. With the opening of the excited bend state we find a multimodal HCl rotational distribution. We rationalize these results using a simple Franck–Condon argument. © 2000 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1308049
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Elementary Reaction Mechanism for Growth of Diamond (100) Surfaces from Methyl Radicals (1994)
    s.l. : American Chemical Society
    The @journal of physical chemistry 〈Washington, DC〉 98 (1994), S. 7073-7082 
    Details
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/j100079a030
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Chemistry of Acetylene on Diamond (100) Surfaces (1995)
    s.l. : American Chemical Society
    The @journal of physical chemistry 〈Washington, DC〉 99 (1995), S. 5616-5625 
    Details
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/j100015a053
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Elementary reaction mechanism of diamond growth from acetylene (1994)
    s.l. : American Chemical Society
    The @journal of physical chemistry 〈Washington, DC〉 98 (1994), S. 8-11 
    Details
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/j100052a003
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Theoretical study of the photodetachment spectroscopy of the IHBr and IDBr anions (2000)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 113 (2000), S. 9479-9487 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: The coupled-cluster method with a large basis set with quasi-relativistic effective core potentials on the halogens was utilized to investigate the ground electronic state X 1Σ+ of the IHBr anion. A semi-global, three-dimensional potential energy surface was obtained via spline interpolation of ab initio data. Variational rovibrational calculations were carried out with this potential energy surface, and assignment of fundamentals and low-lying overtones, as well as combination bands, is presented for IH(D)Br anions. Photodetachment spectra for IH(D)Br−+hν→[IH(D)Br]+e− were computed using three-dimensional time-independent real and complex L2 methods and a recently developed real L2 wave packet propagation technique; all methods employed a previous London–Eyring–Polanyi–Sato empirical potential for the neutral system. Well resolved fine structure is found in photodetachment spectra of IHBr−. This structure is assigned to bending excitation based on analysis of the wave functions and the neutral potential energy surface near the Franck–Condon region. This fine structure is largely eliminated in the IDBr− spectrum. The photodetachment spectrum for the first excited asymmetric stretch of IHBr− shows a new feature that is associated with sampling of the transition state region of the neutral surface. Spin-orbit corrected multi-reference configuration interaction calculations indicate that the first excited electronic state is only about 0.06 eV above the ground electronic state of the neutral IHBr system in the Franck–Condon region. The model empirical potential used in the calculations of photodetachment spectra is shown to have roughly the average behavior of these two ab initio potentials. © 2000 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1319877
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    A reduced dimensionality quantum calculation of the reaction of H2 with diamond (111) surface (2000)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 113 (2000), S. 779-788 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: We present a reduced dimensionality quantum dynamics study of the hydrogen abstraction reaction on a semirigid (111) diamond surface, Cd+H2(v,j,m)→CdH+H. A nine-dimensional potential energy surface is developed by combining a London–Eyring–Polanyi–Sato potential based on ab initio data with nonbonded and surface interactions. Four reactive degrees of freedom are treated explicitly using a recently developed wave packet approach in a real L2 basis, and the total reaction probabilities for initial states v=0–1, j=0–11, and m=0–4 are calculated over a large total energy range. The remaining five degrees of freedom are treated using energy-shift approximations, and the full cumulative reaction probability is obtained and from it the full thermal rate constant. Comparison with conventional transition state theory indicates that at 300 K tunneling accounts for 90% of the rate constant and remains significant even at high temperatures. Dynamical corrections to transition state theory become important above 1000 K. At 1200 K the tunneling and dynamical corrections nearly cancel each other and the transition state theory rate constant agrees very well with quantum rate constant. The coupling of surface and reactive modes has only a minor, less then 15%, effect on the rate constants, provided that the energetics for the relaxed surface are incorporated into the potential. The thermal rate for H abstraction from diamond, obtained from detailed balance, is in good agreement with experimental data. Under typical chemical vapor deposition conditions the thermal rate for H abstraction by diamond active sites is found to be 100 slower than the rate of competitive reaction, H addition to diamond active sites. © 2000 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.481852
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    A comparative study of the quantum dynamics and rate constants of the O(3P)+HCl reaction described by two potential surfaces (2000)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 113 (2000), S. 227-236 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: Wave packet calculations, using direct and damped-L2 real propagation methods, of initial state-resolved and cumulative reaction probabilities for the O(3P)+HCl(1Σ+)→OH(2Π)+Cl(2P) reaction are reported. Results are obtained using the recently developed "S4" potential surface of Ramachandran and co-workers and, for comparison, the earlier Koizumi, Schatz, and Gordon (KSG) potential energy surface. Most calculations are for total angular momentum J=0, although some J〉0 centrifugal sudden results are also obtained. The thermal rate constant and the rate constant for HCl(v=1) are obtained from the J=0 cumulative reaction probability and J-K-shifting, using standard transition-state rotation constants. This type of shifting is justified by examining limited centrifugal sudden calculations. The S4 surface is shown to yield some surprising results. For example, despite a significantly higher ground state adiabatic barrier than the KSG surface, the thermal rate constant is not significantly different from one obtained with the KSG surface, although the one for the vibrationally excited HCl is. © 2000 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.481789
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    An accurate ab initio HOCl potential energy surface, vibrational and rotational calculations, and comparison with experiment (1998)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 109 (1998), S. 2662-2671 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: Accurate ab initio multireference configuration interaction (CI) calculations with large correlation-consistent basis sets are performed for HOCl. After extrapolation to the complete basis set limit, the ab initio data are precisely fit to give a semiglobal three-dimensional potential energy surface to describe HOCl→Cl+OH from high overtone excitation of the OH-stretch. The average absolute deviation between the ab initio and fitted energies is 4.2 cm−1 for energies up to 60 kcal/mol relative to the HOCl minimum. Vibrational energies of HOCl including the six overtones of the OH-stretch are computed using a vibrational-Cl method on the fitted potential and also on a slightly adjusted potential. Near-spectroscopic accuracy is obtained using the adjusted potential; the average absolute deviation between theory and experiment for 19 experimentally reported states is 4.8 cm−1. Very good agreement with experiment is also obtained for numerous rotational energies for the ground vibrational state, the ClO-stretch fundamental, and the fifth overtone of the OH-stretch. © 1998 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.476865
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Complex L2 calculation of the variation of resonance widths of HOCl with total angular momentum (1999)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 111 (1999), S. 4933-4941 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: Complex L2 calculations of the variation of the resonance width of HOCl(6νOH)→Cl+OH with total angular momentum, J, are reported, using a recently developed, accurate ab initio potential energy surface [S. Skokov, J. M. Bowman, and K. A. Peterson, J. Chem. Phys. 109, 2662 (1998)]. The calculations are carried out using the adiabatic rotation approximation for the overall rotation and a truncation/recoupling method for the vibrational states. An ab initio calculation of the J and K dependence of the intensity of the absorption spectrum of the Q branch in the neighborhood of the 2νOH→6νOH transition is presented, and compared to results of recent experiments of Rizzo and co-workers. The variation of the resonance width of the 6,0,0 and the 3,8,0 states with J and K is presented, and comparisons with recent double-resonance experiments of the Rizzo and Sinha groups for the 6,0,0 state show encouraging qualitative agreement. The fluctuations of the dissociation rate with J is shown to be due to rotation-induced coupling of the 6νOH state to a dense set of highly excited OCl stretch states. A simple model describing the coupling of 6νOH with background states, using a coupling constant of 0.05 cm−1 is shown to give a qualitatively correct picture of the fluctuation of the resonance width with J. Finally, the energies of many nonoverlapping resonances, some of which are assigned, for J=18 and K=0 are presented and compared to Rice–Ramsperger–Kassel–Marcus (RRKM) theory. It is found that due to slow, rate limiting, intramolecular vibrational relaxation the RRKM overestimates the average dissociation rate by an order of magnitude. © 1999 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.479752
    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...