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
  • American Institute of Physics (AIP)  (3)
  • 1
    Electronic Resource
    Electronic Resource
    The generation and use of delocalized internal coordinates in geometry optimization (1996)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 105 (1996), S. 192-212 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: Following on from the earlier work of Pulay and Fogarasi [J. Chem. Phys. 96, 2856 (1992)] we present an alternative definition of natural internal coordinates. This set of delocalized internal coordinates can be generated for any molecular topology, no matter how complicated, and is fully nonredundant. Using an appropriate Schmidt-orthogonalization procedure, all standard bond length, bond angle, and dihedral angle constraints can be imposed within our internal coordinate scheme. Combinatorial constraints (in which sums or differences of stretches, bends, and torsions remain constant) can also be imposed. Optimizations on some fairly large systems (50–100 atoms) show that delocalized internal coordinates are far superior to Cartesians even with reliable Hessian information available at the starting geometry. © 1996 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.471864
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    The effect of grid quality and weight derivatives in density functional calculations (1994)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 101 (1994), S. 8894-8902 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: Full density functional geometry optimizations on hydrogen peroxide and heptane/dimethyl pentane using six different numerical grids are presented. The grids vary in quality and gradients are calculated (1) assuming a fixed grid and no weight derivatives, and (2) with full allowance for a "moving'' atom-centered grid and inclusion of the weight derivatives. The results clearly demonstrate that accurate energies and geometries can be obtained with around 3500 points per atom for medium-sized systems (up to say 30 atoms) without the necessity of including the weight derivatives. The latter only begin to influence the results for grids which are of insufficient quality to guarantee reliable values in any case.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.468081
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Binding energies, molecular structures, and vibrational frequencies of transition metal carbonyls using density functional theory with gradient corrections (1994)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 100 (1994), S. 5785-5791 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: The performance of the density functional theory (DFT) methods with different gradient corrections as an approach for the computation of transition metal complexes has been evaluated. As a test, the structures, binding energies, and vibrational frequencies of a series of binary transition metal carbonyl complexes were calculated. Comparison with previous studies shows that the gradient correction significantly improves the performance of the DFT schemes, and that the results obtained generally match the quality of the data obtained from coupled cluster and pair functional methods.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.467142
    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...