A Wannier function based ab initio Hartree-Fock approach extended to polymers: applications to the LiH chain and trans-polyacetylene

TL;DR

This paper extends a Wannier function based ab initio Hartree-Fock method to one-dimensional polymers, demonstrating its effectiveness for covalent systems like LiH chains and trans-polyacetylene with accurate results.

Contribution

It is the first application of this approach to one-dimensional covalent systems, showing its broad applicability and accuracy.

Findings

Excellent agreement with Bloch orbital methods

Accurate cohesive energies and lattice parameters

Detailed analysis of Wannier function localization

Abstract

A recently proposed ab initio Hartree-Fock approach aimed at directly obtaining the Wannier functions of a crystalline insulator is applied to polymers. The systems considered are the LiH chain and trans-polyacetylene. In addition to being the first application of our approach to one-dimensional systems, this work also demonstrates its applicability to covalent systems. Both minimal as well as extended basis sets were employed in the present study and excellent agreement was obtained with the Bloch orbital based approaches. Cohesive energies, optimized lattice parameters and the band structure are presented. Localization characteristics of the Wannier functions are also discussed.