Systematic Improvement of Density Functionals through Parameter-Free Hybridization Schemes.

Area of Science:

• Quantum Chemistry
• Computational Materials Science

Background:

• Density Functional Theory (DFT) is a cornerstone of modern electronic structure calculations.
• The accuracy of DFT methods is critically dependent on the chosen exchange-correlation functional.
• Hybridization schemes offer a promising avenue for enhancing DFT accuracy.

Purpose of the Study:

• To investigate the impact of hybridization schemes on DFT accuracy.
• To mathematically formulate and test models connecting noninteracting and interacting particle systems.
• To evaluate the universality of proposed HYB0 and QIDH hybridization models.

Main Methods:

• Developed a mathematical formulation using an integrand for hybridization.
• Assessed numerous exchange-correlation functionals with HYB0 and QIDH models.
• Validated against established benchmark datasets: AE6, G2/148, and S22.

Main Results:

• Hybridization schemes markedly decrease error bars and standard deviation compared to nonhybrid DFT.
• The observed improvement surpasses variations from different density functionals.
• HYB0 and QIDH models demonstrate a significant reduction in prediction errors.

Conclusions:

• The HYB0 and QIDH hybridization models offer a pathway to more accurate DFT calculations.
• These models show potential for universal application across various chemical systems.
• Hybridization schemes represent a fundamental aspect for achieving ultimate accuracy in DFT.