Performance of Range Separated Hybrids: Study within BECKE88 family and Semilocal Exchange Hole based Range Separated Hybrid

TL;DR

This paper develops a new range separated hybrid functional based on a semilocal exchange hole, demonstrating improved accuracy in thermodynamic and reaction barrier properties compared to existing BECKE88 family functionals.

Contribution

It introduces a novel range separated hybrid functional using a density matrix expansion based exchange hole with a strong physical basis, enhancing property predictions.

Findings

Improved fractional occupation number properties.

Accurate hydrogen and non-hydrogen reaction barrier heights.

Enhanced thermochemical accuracy.

Abstract

A long range corrected range separated hybrid functional is developed based on the density matrix expansion (DME) based semilocal exchange hole with Lee-Yang-Parr (LYP) correlation. An extensive study involving the proposed range separated hybrid for thermodynamic as well as properties related to the fractional occupation number is compared with different BECKE88 family semilocal, hybrid and range separated hybrids. It has been observed that using Kohn-Sham kinetic energy dependent exchange hole several properties related to the fractional occupation number can be improved without hindering the thermochemical accuracy. The newly constructed range separated hybrid accurately describe the hydrogen and non-hydrogen reaction barrier heights. The present range separated functional has been constructed using full semilocal meta-GGA type exchange hole having exact properties related to exchange hole therefore, it has a strong physical basis.