Møller-Plesset Adiabatic Connection Theory for Diverse Noncovalent Interactions

Area of Science:

• Quantum chemistry
• Computational physics
• Materials science

Background:

• Møller-Plesset adiabatic connection (MPAC) theory offers a robust method for approximating wave function-based correlation energy.
• Accurate modeling of noncovalent interactions (NCIs) is crucial for understanding molecular behavior.

Purpose of the Study:

• To evaluate the performance of approximate MPAC functionals for describing NCIs.
• To introduce and validate a new MPAC functional (MPAC25) for improved NCI modeling.

Main Methods:

• Development and application of approximate Møller-Plesset adiabatic connection (MPAC) functionals.
• Benchmarking against MP2 and dispersion-corrected density functional theory (DFT+DISP) methods.
• Testing on diverse systems including charged and charge-transfer complexes, and abnormal NCIs.

Main Results:

• Approximate MPAC functionals consistently outperform MP2 and DFT+DISP for various NCIs.
• MPAC functionals achieve near-chemical accuracy, even for challenging abnormal NCIs where DFT+DISP fails.
• The new MPAC25 functional demonstrates equal effectiveness for neutral and charged NCIs on DES15K benchmarks.

Conclusions:

• MPAC functionals provide a powerful and accurate approach for describing a wide range of NCIs.
• MPAC methods offer a significant advancement for predictive simulations of molecular interactions.
• Further development of MPAC theory holds promise for complex molecular systems.