Automated high-throughput Wannierisation

Valerio Vitale,Nicola Marzari,Antimo Marrazzo,Jonathan R Yates,Giovanni Pizzi,Arash A Mostofi

doi:10.1038/s41524-020-0312-y

Abstract

Maximally-localised Wannier functions (MLWFs) are routinely used to compute from first-principles advanced materials properties that require very dense Brillouin zone integration and to build accurate tight-binding models for scale-bridging simulations. At the same time, high-throughput (HT) computational materials design is an emergent field that promises to accelerate reliable and cost-effective design and optimisation of new materials with target properties. The use of MLWFs in HT workflows has been hampered by the fact that generating MLWFs automatically and robustly without any user intervention and for arbitrary materials is, in general, very challenging. We address this problem directly by proposing a procedure for automatically generating MLWFs for HT frameworks. Our approach is based on the selected columns of the density matrix method and we present the details of its implementation in an AiiDA workflow. We apply our approach to a dataset of 200 bulk crystalline materials that span a wide structural and chemical space. We assess the quality of our MLWFs in terms of the accuracy of the band-structure interpolation that they provide as compared to the band-structure obtained via full first-principles calculations. Finally, we provide a downloadable virtual machine that can be used to reproduce the results of this paper, including all first-principles and atomistic simulations as well as the computational workflows.

Highlights

The combination of modern high-performance computing, robust and scalable software for first-principles electronic structure calculations, and the development of computational workflow management platforms, has the potential to accelerate the design and discovery of materials with tailored properties using firstprinciples high-throughput (HT) calculations[1,2,3,4].Wannier functions (WFs) play a key role in contemporary stateof-the-art first-principles electronic structure calculations
SðkÞ are defined as the span unitary transformation on the junki that span F ðkÞ: An alternative method to the SMV approach described in the “Introduction” has recently been proposed by Damle et al.[20,21] in the form of the aforementioned selected columns of the density matrix (SCDM) algorithm
Our aim is to leverage on the ability of SCDM to automatically generate a good set of localised functions, and to use these to seed the MV algorithm for the minimisation of the total spread functional, which will give in turn an automated protocol to generate maximally-localised Wannier functions (MLWFs)

Summary

Introduction

Wannier functions (WFs) play a key role in contemporary stateof-the-art first-principles electronic structure calculations. They provide a means by which to bridge lengthscales by enabling the transfer of information from the atomic scale (e.g., densityfunctional theory and many-body perturbation theory calculations) to mesoscopic scales at the level of functional nano-devices (e.g., tight-binding calculations with a first-principles-derived WF basis)[5,6]. In the case of entangled bands[10], this tends not to be the case and the choice of initial guess strongly affects the quality of the final MLWFs, presenting a challenge to the development of a generalpurpose approach to generating MLWFs automatically without user intervention

Objectives

Methods

Results