Optimization Algorithm for the Generation of ONCV Pseudopotentials

TL;DR

This paper introduces an optimization algorithm to generate high-quality ONCV pseudopotentials for elements up to bismuth, ensuring good agreement with all-electron calculations and efficient plane-wave cutoffs.

Contribution

It presents a novel optimization approach using a quality function and Nelder-Mead algorithm to systematically generate pseudopotentials for most elements.

Findings

Pseudopotentials show excellent agreement with all-electron results.

Achieve accurate results with a plane-wave cutoff around 60 Ry.

Method effectively automates pseudopotential generation for many elements.

Abstract

We present an optimization algorithm to construct pseudopotentials and use it to generate a set of Optimized Norm-Conserving Vanderbilt (ONCV) pseudopotentials for elements up to Z=83 (Bi) (excluding Lanthanides). We introduce a quality function that assesses the agreement of a pseudopotential calculation with all-electron FLAPW results, and the necessary plane-wave energy cutoff. This quality function allows us to use a Nelder-Mead optimization algorithm on a training set of materials to optimize the input parameters of the pseudopotential construction for most of the periodic table. We control the accuracy of the resulting pseudopotentials on a test set of materials independent of the training set. We find that the automatically constructed pseudopotentials provide a good agreement with the all-electron results obtained using the FLEUR code with a plane-wave energy cutoff of approximately 60 Ry.