Journal ArticleDOI
Refinement of the Asymptotic Z Expansion for the Ground-State Correlation Energies of Atomic Ions
TLDR
In this article, the exact high-Z limit for atomic ions with up to 18 electrons was determined using degenerate second-order perturbation theory for the correlation contribution to the energies of atomic ion with 3−18 electrons.Abstract:
Davidson and co-workers (Phys. Rev. A 1991, 44, 7071; 1993, 47, 3649) have estimated the nonrelativistic correlation energies and relativistic corrections to ionization potentials for atomic ions with up to 18 electrons. However, due to the lack of theoretical values for the high-Z limits and lack of more accurate compilations of experimental ionization potentials, the analysis for 11−18 electrons required further investigation. In this work, we have accurately determined the exact high-Z limit employing degenerate second order perturbation theory for the correlation contribution to the energies of atomic ions with 3−18 electrons. We have also incorporated the experimental compilation of the electron affinity data of Hotop and Lineberger for the low-Z limit. This high-Z limit is compared with the results of the LYP correlation energy functional. The LYP correlation functional is also compared with the correlation energy of electrons in an external harmonic potential of infinite force constant.read more
Citations
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Journal ArticleDOI
Perspective: Fifty years of density-functional theory in chemical physics
TL;DR: This Perspective outlines the history, basic concepts, and present status of KS-DFT in chemical physics, and offers suggestions for its future development.
Journal ArticleDOI
A new one-parameter progressive colle-salvetti-type correlation functional
TL;DR: One-parameter progressive (OP) functional as mentioned in this paper is a simplified correlation functional based on the Colle-Salvetti correlation functional, which can be adapted to any kind of exchange functional.
Journal ArticleDOI
Highly accurate coupled-cluster singlet and triplet pair energies from explicitly correlated calculations in comparison with extrapolation techniques
TL;DR: In this paper, the CCSD valence shell correlation energies of the systems CH2 (<1A1 state), H2O, HF, N2, CO, Ne, and F2 are computed by means of standard calculations with correlation-consistent basis sets of the type cc-pVxZ (x = D, T, Q, 5, 6, 6) and explicitly correlated coupled-cluster calculations (CCSD-R12/B) with large uncontracted basis sets.
Book ChapterDOI
Orbital-Free Kinetic-Energy Density Functional Theory
TL;DR: In this paper, it is shown that the last frontier in DFT is a better representation of the kinetic energy solely in terms of the density, and the density can be solved directly from the TF-HK equation.
Journal ArticleDOI
The extended Perdew-Burke-Ernzerhof functional with improved accuracy for thermodynamic and electronic properties of molecular systems
Xin Xu,William A. Goddard +1 more
TL;DR: The four free parameters in PBE theory are optimized against experimental atomic data and the van der Waals interaction properties of Ne(2), leading to the xPBE extended functional, which significantly outperforms PBE for thermochemical properties and significantly enlarges the field of applications available for pure DFT.
References
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Journal ArticleDOI
Development of the Colle-Salvetti correlation-energy formula into a functional of the electron density
TL;DR: Numerical calculations on a number of atoms, positive ions, and molecules, of both open- and closed-shell type, show that density-functional formulas for the correlation energy and correlation potential give correlation energies within a few percent.
Journal ArticleDOI
Density-functional approximation for the correlation energy of the inhomogeneous electron gas
TL;DR: Numerical results for atoms, positive ions, and surfaces are close to the exact correlation energies, with major improvements over the original LM approximation for the ions and surfaces.
Journal ArticleDOI
Binding energies in atomic negative ions
Hartmut Hotop,W. C. Lineberger +1 more
TL;DR: A survey of the electron affinity determinations for the elements up to Z=85 is presented, and based upon these data, a set of recommended electron affinities is established.
Journal ArticleDOI
Correlation energy of an inhomogeneous electron gas: A coordinate‐space model
TL;DR: In this paper, a coordinate-space model for dynamical correlations in an inhomogeneous electron gas is presented. But the model treats opposite spin and same spin pairs separately, and it also accounts properly for correlation contributions to the kinetic energy.
Journal ArticleDOI
Über den Grundterm der Zweielektronenprobleme von H - , He, Li + , Be ++ usw.
TL;DR: Theoretically bestimmte Korrektionsglieder, d. h. as mentioned in this paper, fordert nur die Kenntnis der Eigenfunktion nullter Naherung.