Assessment of SAPT(DFT) with meta-GGA functionals

Area of Science:

• Computational Chemistry
• Quantum Chemistry
• Materials Science

Background:

• Symmetry-Adapted Perturbation Theory (SAPT) is a method for calculating intermolecular interaction energies.
• Density Functional Theory (DFT) functionals are crucial for accurate SAPT calculations.
• Meta-GGA functionals offer a potential improvement over traditional GGA functionals in DFT.

Purpose of the Study:

• To evaluate the performance of various meta-GGA functionals in SAPT calculations.
• To compare meta-GGA based SAPT (SAPT(DFT)) with a benchmark coupled-cluster variant (SAPT(CCSD)).
• To assess the suitability of meta-GGAs for describing different types of molecular interactions.

Main Methods:

• Term-by-term comparison of SAPT(DFT) with SAPT(CCSD) for various molecular complexes.
• Inclusion of nonempirical meta-GGAs: TPSS, revTPSS, MVS, SCAN, SCAN0 (with/without Asymptotic Correction - AC).
• Testing of a range-separated meta-GGA: LC-PBETPSS.

Main Results:

• AC-corrected meta-GGAs (except MVS) improve SAPT(DFT) energy component predictions compared to GGA.
• No meta-GGA outperformed the hybrid GGA approach SAPT(PBE0AC).
• SCAN- and TPSS-based electrostatic energies showed excellent agreement (within 5%) with reference data.
• SCAN0 is suitable for SAPT without AC; LC-PBETPSS performs reliably.

Conclusions:

• Meta-GGAs represent progress for SAPT(DFT), particularly for electrostatic interactions.
• Hybrid functionals are still preferred for overall accuracy in SAPT calculations.
• SCAN0 and LC-PBETPSS show particular promise for future SAPT studies.