Spin-Component-Scaled Double-Hybrid Density Functionals with Nonlocal van der Waals Correlations for Noncovalent...

Area of Science:

• Computational chemistry
• Quantum chemistry
• Materials science

Background:

• Density functional theory (DFT) is crucial for modeling molecular interactions.
• Accurate description of noncovalent interactions remains a challenge in computational chemistry.
• Double-hybrid density functionals (DHDFs) offer improved accuracy but require further refinement.

Purpose of the Study:

• To incorporate nonlocal (NL) van der Waals correlation into spin-component and spin-opposite scaled DHDFs.
• To evaluate the performance of these modified DHDFs for noncovalent interactions.
• To assess their accuracy in describing charge transfer interactions.

Main Methods:

• Optimization of short-range attenuation parameters for NL-corrected DHDFs using the S66 database.
• Development of four new NL-corrected DHDFs: PWPB95-NL, DSD-BLYP-NL, DSD-PBEP86-NL, and DOD-PBEP86-NL.
• Benchmarking against established databases including S22B, NCCE31, and ADIM6.

Main Results:

• The integration of NL correlation with scaled DHDFs significantly enhances the description of noncovalent interactions.
• Optimized DHDFs demonstrate improved accuracy across multiple benchmark datasets.
• A notable deficiency was observed in the performance of these NL-corrected DHDFs for charge transfer interactions.

Conclusions:

• The combination of NL correlation and spin-scaled DHDFs presents a successful strategy for modeling noncovalent interactions.
• Further development is needed to address the limitations in describing charge transfer phenomena.
• These findings contribute to the advancement of accurate computational methods for chemical systems.