Wavefunction-based correlated ab initio calculations on crystalline solids

TL;DR

This paper introduces a wavefunction-based method for correlated ab initio calculations on infinite crystalline insulators, utilizing Wannier functions to efficiently evaluate electron correlation effects with rapid convergence.

Contribution

It presents a novel approach combining Wannier functions with localized correlation calculations for infinite solids, improving computational efficiency and accuracy.

Findings

Method yields rapidly convergent results for LiH crystal

Effective in capturing electron correlation effects in solids

Applicable to other crystalline insulators

Abstract

We present a wavefunction-based approach to correlated ab initio calculations on crystalline insulators of infinite extent. It uses the representation of the occupied and the unoccupied (virtual) single-particle states of the infinite solid in terms of Wannier functions. Electron correlation effects are evaluated by considering virtual excitations from a small region in and around the reference cell, keeping the electrons of the rest of the infinite crystal frozen at the Hartree-Fock level. The method is applied to study the ground state properties of the LiH crystal, and is shown to yield rapidly convergent results.