Library

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
    Local space approximation for treatment of impurities in polymers. Solitons in polyacetylene (1987)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 86 (1987), S. 1624-1631 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: The local space approximation (LSA) is applied to neutral and positive solitons, S0 and S+, in polyacetylene. In the treatment presented here a solitonic fragment is embedded between two finite polyene side chains. On the basis of INDO model calculations we conclude that electronic structure properties of the infinite system can be represented with chemical accuracy by a C9 solitonic fragment bonded to C4 or C6 side chains in S0 and C10 side chains in S+. The local space for each bond is defined by a C6H4 interaction complex augmented, for S+, with the π orbital of one additional carbon on the solitonic fragment and three additional carbons on the side chain. These results establish the feasibility of using the LSA method to carry out accurate ab initio Hartree–Fock and CI calculations based on a finite chain model for the soliton.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.452202
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Comparison between local space approximation and finite cluster treatments of chemisorption on metals (1988)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 88 (1988), S. 1019-1025 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: The local space approximation (LSA) method is applied to a model Hamiltonian describing the chemisorption of a hydrogen atom onto a transition metal (0,0,1) surface. In the LSA method a finite cluster defined by a local (orbital) space is properly embedded into the complete system. Without embedding the calculated binding energy, ΔEb oscillates strongly as the size of the cluster increases, and even when 200–250 metal atoms are included the convergence is unsatisfactory. On the other hand, the LSA treatment yields rapid monotonic convergence. Using a systematic buildup of the local space the error in ΔEb is 4.4 kcal/mole out of 80.5 for a 10 metal atom cluster; that error decreases steadily to 1.8 kcal/mole for a cluster containing 30 metal atoms. Extrapolation reduces the error for all clusters between 18 and 71 metal atoms by about 0.6 kcal/mole.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.454268
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Accurate local-space treatment of hydrogen bonding in large systems (1986)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 29 (1986), S. 1209-1222 
    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: Tests of the local-space approximation for electronic structure are carried out on a variety of hydrogenbonded systems. Regardless of size they are all found to be well localized in the sense of this approximation. For a local space defined by the valence atomic orbitals on X—H ··· Y, one obtains a bond energy within 6% of the “exact” full-space value. The potential energy surface and the electronic charge distribution are also accurately determined. In contrast with cluster models the local-space approximation satisfactorily accounts for long-range electrostatic and polarization effects.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560290519
    Library Location Call Number Volume/Issue/Year 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...