Ab initio real-space Hartree-Fock and correlated approach to optical dielectric constants of crystalline insulators

TL;DR

This paper introduces a real-space, Wannier function-based method to calculate optical dielectric constants of crystalline insulators at both Hartree-Fock and correlated levels, achieving excellent experimental agreement for the first time in bulk solids.

Contribution

It presents the first ab initio correlated approach using real-space Wannier functions to compute dielectric constants of bulk insulators.

Findings

Correlated calculations match experimental dielectric constants.

Method successfully applied to LiF, LiCl, MgO, Li2O.

First such calculations for bulk solids.

Abstract

In this paper we present an approach aimed at calculating the optical dielectric constant of crystalline insulators both at the Hartree-Fock, and correlated levels. Our scheme employs a real-space methodology, employing Wannier functions as the basic building blocks. The scheme has been applied to compute the optical dielectric constants of LiF, LiCl, MgO, and Li2O. In all the cases, results of correlated calculations, based upon systematic many-body corrections beyond Hartree-Fock, exhibit excellent agreement with the experiments. To the best of our knowledge, the calculations presented here are the first of their kind for bulk solids.