Maximally Localized Wannier Functions within the FLAPW formalism

TL;DR

This paper presents the implementation of maximally localized Wannier functions within the FLAPW method, enabling detailed electronic structure analysis for various materials and geometries, including effects of spin-orbit coupling.

Contribution

The authors develop and demonstrate a new implementation of Wannier functions within the FLAPW formalism, applicable to bulk, film, and 1D systems, with comprehensive comparisons and analysis.

Findings

Accurate Wannier functions for SrVO3, BaTiO3, graphene, and Pt chains.

Good agreement of ferroelectric polarization with existing results.

Insights into spin-orbit coupling effects on Wannier functions.

Abstract

We report on the implementation of the Wannier Functions (WFs) formalism within the full-potential linearized augmented plane wave method (FLAPW), suitable for bulk, film and one-dimensional geometries. The details of the implementation, as well as results for the metallic SrVO3, ferroelectric BaTiO3 grown on SrTiO3, covalently bonded graphene and a one-dimensional Pt-chain are given. We discuss the effect of spin-orbit coupling on the Wannier Functions for the cases of SrVO3 and platinum. The dependency of the WFs on the choice of the localized trial orbitals as well as the difference between the maximally localized and "first-guess" WFs are discussed. Our results on SrVO3 and BaTiO3, e.g. the ferroelectric polarization of BaTiO3, are compared to results published elsewhere and found to be in excellent agreement.