Generalized Wannier functions: a comparison of molecular electric dipole polarizabilities

TL;DR

This paper compares nonorthogonal generalized Wannier functions (NGWFs) with maximally localized Wannier functions (MLWFs), showing NGWFs can efficiently and accurately compute molecular electric dipole polarizabilities without post-processing.

Contribution

It demonstrates that NGWFs can be used directly to compute dielectric properties with accuracy comparable to MLWFs, simplifying the process.

Findings

NGWFs can be optimized in situ during ground-state calculations

NGWFs provide polarizability results comparable to MLWFs

Using NGWFs eliminates the need for post-processing optimization

Abstract

Localized Wannier functions provide an efficient and intuitive means by which to compute dielectric properties from first principles. They are most commonly constructed in a post-processing step, following total-energy minimization. Nonorthogonal generalized Wannier functions (NGWFs) [Skylaris et al., Phys. Rev. B 66, 035119 11 (2002); Skylaris et al., J. Chem. Phys. 122, 084119 (2005)] may also be optimized in situ, in the process of solving for the ground-state density. We explore the relationship between NGWFs and orthonormal, maximally localized Wannier functions (MLWFs) [Marzari and Vanderbilt, Phys. Rev. B 56, 12847 (1997); Souza, Marzari, and Vanderbilt, ibid. 65, 035109 (2001)], demonstrating that NGWFs may be used to compute electric dipole polarizabilities efficiently, with no necessity for post-processing optimization, and with an accuracy comparable to MLWFs.