Orbital currents in the Colle-Salvetti correlation energy functional and the degeneracy problem
Materials Science
2007-07-31 v2
Abstract
Popular density functionals for the exchange-correlation energy typically fail to reproduce the degeneracy of different ground states of open-shell atoms. As a remedy, functionals which explicitly depend on the current density have been suggested. We present an analysis of this problem by investigating functionals that explicitly depend on the Kohn-Sham orbitals. Going beyond the exact-exchange approximation by adding correlation in the form of the Colle-Salvetti functional we show how current-dependent terms enter the Colle-Salvetti expression and their relevance is evaluated. A very good description of the degeneracy of ground-states for atoms of the first and second row of the periodic table is obtained.
Keywords
Cite
@article{arxiv.0704.1593,
title = {Orbital currents in the Colle-Salvetti correlation energy functional and the degeneracy problem},
author = {S. Pittalis and S. Kurth and S. Sharma and E. K. U. Gross},
journal= {arXiv preprint arXiv:0704.1593},
year = {2007}
}