Density matrix expansion based semi-local exchange hole applied to range separated density functional theory

TL;DR

This paper introduces a new long-range corrected density functional that combines a DME-based exchange hole with HF exchange, improving accuracy across various molecular properties.

Contribution

It develops a novel long-range corrected scheme integrating DME-based meta-GGA exchange with HF exchange, enhancing functional performance.

Findings

Performs well in thermochemistry tests

Accurately models noncovalent interactions

Improves barrier height predictions

Abstract

Exchange hole is the principle constituent in density functional theory, which can be used to accurately design exchange energy functional and range separated hybrid functionals coupled with some appropriate correlation. Recently, density matrix expansion (DME) based semi-local exchange hole proposed by Tao-Mo gained attention due to its fulfillment of some exact constraints. We propose a new long-range corrected (LC) scheme that combines meta-generalized gradient approximation (meta-GGA) exchange functionals designed from DME exchange hole coupled with the ab-initio Hartree-Fock (HF) exchange integral by separating the Coulomb interaction operator using standard error function. Associate with Lee-Yang-Parr (LYP) correlation functional, assessment and benchmarking of our functional using well-known test set shows that it performs remarkably well for a broad range of molecular properties, such as thermochemistry, noncovalent interaction and barrier height of chemical reactions.