Towards a quantum-chemical description of crystalline insulators: A Wannier-function-based Hartree-Fock study of Li2O and Na2O

TL;DR

This paper applies a Wannier-function-based Hartree-Fock method to crystalline insulators Li2O and Na2O, achieving accurate structural and energetic properties and highlighting its potential for electron-correlation studies in solids.

Contribution

It introduces and validates a Wannier-function-based approach for Hartree-Fock calculations on crystalline insulators, showing excellent agreement with traditional methods.

Findings

Cohesive energies match traditional Hartree-Fock results.

Lattice constants and bulk moduli are accurately reproduced.

Method shows promise for electron-correlation calculations in solids.

Abstract

A recently proposed approach for performing electronic-structure calculations on crystalline insulators in terms of localized orthogonal orbitals is applied to the oxides of lithium and sodium, Li2O and Na2O. Cohesive energies, lattice constants and bulk moduli of the aforementioned systems are determined at the Hartree-Fock level, and the corresponding values are shown to be in excellent agreement with the values obtained by a traditional Bloch-orbital-based Hartree-Fock approach. The present Wannier-function-based approach is expected to be advantageous in the treatment of electron-correlation effects in an infinite solid by conventional quantum-chemical methods.