Constructing optimal local pseudopotentials from first principles

TL;DR

This paper introduces a first-principles method to construct and evaluate local pseudopotentials (LPP) from norm-conserving pseudopotentials (NCPP), enhancing the transferability and applicability of LPPs across different chemical environments in large-scale simulations.

Contribution

It establishes a fundamental relation between NCPP and LPP, enabling optimal construction of LPPs from first principles for many elements using the optimized effective potential method.

Findings

LPP can be constructed optimally from NCPP for many elements.

Existence of LPP is intrinsic to elements, independent of construction parameters.

Provides a unified framework for constructing and assessing LPPs from first principles.

Abstract

Local pseudopotential (LPP) is an important component of the orbital free density functional theory (OF-DFT), which is a promising large scale simulation method that can still maintain information of electron state in materials. Up to date, LPP is usually extracted from the solid state DFT calculations. It is unclear how to assess its transferability while applying to a much different chemical environment. Here we reveal a fundamental relation between the first principles norm-conserving PP (NCPP) and the LPP. Using the optimized effective potential method developed for exchange functional, we demonstrate that the LPP can be constructed optimally from the NCPP for a large number of elements. Our theory also reveals that the existence of an LPP is intrinsic to the elements, irrespective to the parameters used for the construction. Our method provides a unified method in constructing and assessing LPP in the framework of first principles pseudopotentials.