Benchmark Data for Noncovalent Interactions in HCOOH···Benzene Complexes and Their Use for Validation of Density...

Area of Science:

• Computational Chemistry
• Physical Chemistry
• Chemical Physics

Background:

• Noncovalent interactions are crucial in molecular systems.
• Accurate prediction of binding energies for complexes like formic acid-benzene is essential for modeling.
• Density functional theory (DFT) methods are widely used but require validation.

Purpose of the Study:

• To establish benchmark energetic data for formic acid-benzene complexes.
• To evaluate the performance of various density functionals and DFT-D methods for these systems.
• To provide reference data for developing and refining computational models.

Main Methods:

• High-level composite approach based on coupled cluster with singles and doubles and perturbative triples (CCSD(T)) calculations.
• Testing of local density functionals (e.g., M06-L, PBEsol, SOGGA) and DFT-D methods (e.g., BLYP-D, PBEsol-D).
• Calculation of binding energies and mean unsigned errors (MUE), with basis set superposition error correction using the counterpoise approach.

Main Results:

• Benchmark binding energies for HCOOH···benzene complexes range from 1.6-4.8 kcal/mol.
• M06-L without dispersion corrections achieved a MUE of 0.15 kcal/mol.
• DFT-D methods, specifically BLYP-D and PBEsol-D, also yielded a MUE of 0.15 kcal/mol.
• Empirical dispersion corrections significantly improved the description of noncovalent interactions.

Conclusions:

• M06-L is a highly accurate local density functional for HCOOH···benzene complexes.
• DFT-D methods with empirical dispersion corrections effectively capture noncovalent interactions.
• The generated benchmark data and intermolecular potentials are valuable for parametrizing force fields and coarse-grained models.