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
    Closed-form expression relating the second-order component of the density functional theory correlation energy to its functional derivative (1998)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 109 (1998), S. 6280-6286 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: For helping to improve approximations to the density-functional exchange-correlation energy, Exc[n], and its functional derivative, the difference between the second-order component of the correlation energy, Ec(2)[n], and the integral ∫dr vc(2)([n];r)n(r), involving its functional derivative, vc(2)([n];r), is given in terms of only the occupied Kohn–Sham orbitals and the exchange potential. The quantity 2Ec(2)[n] is especially significant because it is the initial slope in the adiabatic connection formula for Exc[n]. The analytic expression for 2Ec(2)[n]−∫dr vc(2)([n];r)n(r) is obtained for any spherically symmetric two-electron test density. Numerical examples are presented. © 1998 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.477269
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Properties of electron density and other one-electron observables derived from generalized Hiller–Sucher–Feinberg identities (1998)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 109 (1998), S. 1230-1237 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: A generalization of the Hiller–Sucher–Feinberg (HSF) and Rassolov–Chipman identities for the electron density is presented. A companion expression for the electrostatic potential is derived. Properties of the electron density furnished by the generalized HSF identity are discussed. In particular, the behavior in the vicinity of an arbitrary potential singularity and the long-range asymptotics are analyzed in detail. A simple numerical example is provided to illustrate the new theoretical results. © 1998 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.476674
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Approximate one-electron density matrix functionals for the electron–electron repulsion energy from the hypervirial theorem (1998)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 109 (1998), S. 4156-4163 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: Application of the hypervirial theorem to a certain class of two-electron operators yields the electron–electron repulsion energy as an approximate functional of the Hartree–Fock one-electron reduced density matrix. This functional is entirely parameterized by a single screening function that, upon the assumption of transferability, can be readily retrieved from the known correlation energy of the homogeneous electron gas. Invoking the properties of the actual electronic Hamiltonian, the new formalism explicitly incorporates dispersion effects that are not accounted for by the conventional density functional approaches. Even more importantly, it affords analogous functionals for other variational methods such as Monte Carlo self-consistent field (MC SCF). Since such functionals are bi- and trilinear in the occupied orbitals, their fully analytical computation should be feasible with a carefully chosen approximate representation of the screening function. © 1998 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.477021
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Local-scaling transformations and the direct determination of Kohn–Sham orbitals and potentials for beryllium (1995)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 102 (1995), S. 318-326 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: Local-scaling transformations are used in the present work to obtain accurate Kohn–Sham 1s and 2s orbitals for the beryllium atom by means of a density-constrained variation of the single-determinant kinetic energy functional. An analytic representation of these Kohn–Sham orbitals is given and the quality of the different types of orbitals generated is discussed with particular reference to their kinetic energy and momenta mean values. In addition, we determine the effective Kohn–Sham potential and analyze it in terms of its exchange-only and correlation contributions. © 1995 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.469405
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Polynomial and Padé Representations for the Kinetic Component Tc[ρ] of the Correlation Energy Density Functional (1998)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 69 (1998), S. 513-522 
    Details
    ISSN: 0020-7608
    Keywords: density functional theory ; correlation energy ; kinetic energy ; Chemistry ; Theoretical, Physical and Computational Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Polynomial and Padé representations of the kinetic energy component Tc[ρ] of the correlation energy density functional Ec[ρ] are presented in this article. Two approximate local formulas similar to the Wigner form for Ec[ρ] are investigated for Tc[ρ]. Applications of these formulas along with their two polynomial counterparts are carried out for atoms, ions, and a few simple molecules. Numerical predictions of Tc values are made for these species. Both Hartree-Fock and self-consistent-field densities are used in their evaluations. Recommended at this time is the two-parameter Padé [0, 1] formula Tc[ρ]=∫a0ρ/(1+b0ρ-1/3) dr, with a0=0.1658 and b0=6.102 (atomic units).   © 1998 John Wiley & Sons, Inc. Int J Quant Chem 69: 513-522, 1998
    Additional Material: 8 Tab.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
  • 6
    Electronic Resource
    Electronic Resource
    Local-scaling transformation version of density functional theory (1995)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 56 (1995), S. 285-301 
    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 local-scaling transformation version of density functional theory (LS-DFT) is reviewed. It is shown that in the context of LS-DFT it is possible to construct N-representable energy density functionals and that the theory provides systematic ways for calculating strict upper bounds to the exact energies. The importance of the concept of “orbit” in LS-DFT is indicated and several approaches leading to intraorbit and interorbit optimization are discussed. Results of the application of these optimization procedures to the determination of upper bounds for the ground-state energy of the beryllium atom are given. Also, numerical results are reported on the use of local scaling transformations for the direct solution of the Kohn-Sham equations via the density-constrained minimization of the kinetic energy of a noninteracting system. © 1995 John Wiley & Sons, Inc.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560560413
    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...