Nonlocal Kinetic Energy Density Functionals for Isolated Systems via Local Density Approximation Kernels

TL;DR

This paper introduces a new family of nonlocal kinetic energy density functionals tailored for isolated systems, enabling more accurate and stable orbital-free density functional theory simulations.

Contribution

A generalized scheme to construct nonlocal KEDFs using local density approximation kernels for isolated systems is proposed, expanding applicability of orbital-free DFT.

Findings

Achieves high numerical accuracy for clusters

Demonstrates stability in simulations of isolated systems

Enables practical orbital-free DFT applications

Abstract

Despite a large number of nonlocal kinetic energy density functionals (KEDFs) available for large-scale calculations, most of those nonlocal KEDFs designed for the extended systems cannot be directly applied to isolated systems. In this manuscript, we proposed a generalized scheme to construct nonlocal KEDFs via the local density approximation kernels and construct a family of KEDFs for simulations of isolated systems within orbital-free density functional theory. The performance of KEDFs has been demonstrated by several clusters encompassing Mg, Si and GaAs. The results show that our constructed KEDFs can achieve high numerical accuracy and stability for random clusters, therefore, making orbital-free density functional theory accessible for practical simulations of isolated systems.