First Multireference Correlation Treatment of Bulk Metals

J Chem Theory Comput. 2014 Apr 8;10(4):1698-706. doi: 10.1021/ct401040t. Epub 2014 Mar 6.

Abstract

Existence of the sp-d hybridization of the valence band states of the fcc Ca and Sr in the vicinity of the Fermi level indicates that their electronic wave function can have a multireference (MR) character. We performed a wave-function-based correlation treatment for these materials by means of the method of increments. As opposed to the single-reference correlation treatment (here, coupled cluster), which fails to describe cohesive properties in both cases, employing the MR averaged coupled pair functional, one can achieve almost 100% of the experimental correlation energy.