Correlation energies beyond the random-phase approximation: Inhomogeneous Singwi-Tosi-Land-Sjolander functional applied to spherical atoms and ions
Abstract
The inhomogeneous Singwi, Tosi, Land, and Sjolander (ISTLS) correlation energy functional of Dobson, Wang, and Gould [ Phys. Rev. B 66 081108(R) (2002)] has proved to be successful at predicting correlation energies in semihomogeneous systems, showing promise as a robust "next step" fifth-rung functional by using dynamic correlation to go beyond the limitations of the direct random-phase approximation (dRPA), but with similar numerical scaling with system size. In this work we test the functional on spherically symmetric, neutral, and charged atomic systems and find it gives excellent results (within 2mHa/e- except Be) for ...
View more >The inhomogeneous Singwi, Tosi, Land, and Sjolander (ISTLS) correlation energy functional of Dobson, Wang, and Gould [ Phys. Rev. B 66 081108(R) (2002)] has proved to be successful at predicting correlation energies in semihomogeneous systems, showing promise as a robust "next step" fifth-rung functional by using dynamic correlation to go beyond the limitations of the direct random-phase approximation (dRPA), but with similar numerical scaling with system size. In this work we test the functional on spherically symmetric, neutral, and charged atomic systems and find it gives excellent results (within 2mHa/e- except Be) for the absolute correlation energies of the neutral atoms tested, and good results for the ions (within 4mHa/e- except B+). In all cases it performs better than the dRPA. When combined with the previous successes, these new results point to the ISTLS functional being potentially suitable for high-accuracy, benchmark DFT correlation energy calculations in a wide range of systems.
View less >
View more >The inhomogeneous Singwi, Tosi, Land, and Sjolander (ISTLS) correlation energy functional of Dobson, Wang, and Gould [ Phys. Rev. B 66 081108(R) (2002)] has proved to be successful at predicting correlation energies in semihomogeneous systems, showing promise as a robust "next step" fifth-rung functional by using dynamic correlation to go beyond the limitations of the direct random-phase approximation (dRPA), but with similar numerical scaling with system size. In this work we test the functional on spherically symmetric, neutral, and charged atomic systems and find it gives excellent results (within 2mHa/e- except Be) for the absolute correlation energies of the neutral atoms tested, and good results for the ions (within 4mHa/e- except B+). In all cases it performs better than the dRPA. When combined with the previous successes, these new results point to the ISTLS functional being potentially suitable for high-accuracy, benchmark DFT correlation energy calculations in a wide range of systems.
View less >
Journal Title
Physical Review A
Volume
85
Issue
6
Copyright Statement
© 2012 American Physical Society. This is the author-manuscript version of this paper. Reproduced in accordance with the copyright policy of the publisher. Please refer to the journal's website for access to the definitive, published version.
Subject
Mathematical sciences
Physical sciences
Atomic and molecular physics
Chemical sciences