Automated high-throughput Wannierisation

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-thoughput (HT) computational materials design is an emergent field that promises to accelerate the 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 (SCDM, see SCDM Wannier Functions) and is implemented in an AiiDA workflow.

Purpose of Module

Create a fully-automated protocol based on the SCDM algorithm for the construction of MLWFs, in which the two free parameters are determined automatically (in our HT approach the dimensionality of the disentangled space is fixed by the total number of states used to generate the pseudopotentials in the DFT calculations).

In the paper derived from this work [vitale2019], 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.

[vitale2019]arXiv:1909.00433 [physics.comp-ph]

Background Information

This module is a collaboration between the E-CAM and MaX HPC centres of excellence.

In SCDM Wannier Functions, E-CAM has implemented the SCDM algorithm in the pw2wannier90 interface code between the Quantum ESPRESSO software and the Wannier90 code. We have used this implementation as the basis for a complete computational workflow for obtaining MLWFs and electronic properties based on Wannier interpolation of the BZ, starting only from the specification of the initial crystal structure. We have implemented our workflow within the AiiDA materials informatics platform, and we used it to perform a HT study on a dataset of 200 materials.

Building and Testing

An AiiDA export file is provided with the full provenance of all simulations run in the project.

Source Code

See the Materials Cloud entry. A downloadable virtual machine is provided that allows to reproduce the results of the associated paper and also to run new calculations for different materials, including all first-principles and atomistic simulations and the computational workflows.