A Critical Evaluation of the Hybrid KS DFT Functionals Based on the KS Exchange-Correlation Potentials

Area of Science:

• Quantum Chemistry
• Computational Materials Science
• Theoretical Chemistry

Background:

• Density Functional Theory (DFT) is a cornerstone of modern computational chemistry and materials science.
• Hybrid exchange-correlation (XC) density functional approximations (DFAs) offer improved accuracy but require rigorous evaluation.
• Assessing the quality of hybrid DFAs necessitates fundamental physical quantities.

Purpose of the Study:

• To establish a critical methodology for evaluating hybrid XC-DFAs.
• To assess the quality of 155 hybrid DFAs using fundamental properties.
• To identify key characteristics of high-performing hybrid XC-DFAs.

Main Methods:

• Developed a novel methodology to evaluate hybrid XC-DFAs.
• Calculated XC potentials by inverting self-consistent Kohn-Sham (KS) electron densities.
• Tested 155 hybrid DFAs against Full Configuration Interaction (FCI) and Coupled Cluster (CCSD(T)) reference data.

Main Results:

• A subset of hybrid functionals, particularly those with high Hartree-Fock exchange, yield accurate KS XC potentials.
• The quality of the calculated ionization potential (IP) is strongly correlated with the accuracy of the XC potential.
• XC energy calculations are significantly influenced by functional-driven errors, impacting electron densities.

Conclusions:

• High Hartree-Fock exchange content is crucial for developing accurate hybrid XC-DFAs.
• The developed methodology provides a new framework for constructing improved KS-DFT functionals.
• This work offers valuable insights for the future design of more reliable computational chemistry tools.