NENCI-2021. I. A large benchmark database of non-equilibrium non-covalent interactions emphasizing close...

Area of Science:

• Computational Chemistry
• Quantum Chemistry
• Molecular Modeling

Background:

• Accurate calculation of non-covalent interactions is crucial for understanding chemical and biological processes.
• Existing databases often lack diversity or sufficient sampling of interaction geometries.
• There is a growing demand for high-quality quantum mechanical data.

Purpose of the Study:

• To present NENCI-2021, a comprehensive benchmark database of non-equilibrium non-covalent interaction energies.
• To extend existing databases by including cation-π and anion-π complexes and systematically sampling potential energy surfaces.
• To provide high-quality data for the development and validation of computational methods.

Main Methods:

• Systematic sampling of intermolecular distances and angles for 141 potential energy surfaces.
• Calculation of interaction energies using coupled-cluster with singles, doubles, and perturbative triples/complete basis set (CCSD(T)/CBS) level of theory.
• Symmetry-adapted perturbation theory (SAPT)-based energy decomposition analysis.

Main Results:

• NENCI-2021 contains 7763 benchmark interaction energies spanning a wide range (-38.5 to +186.8 kcal/mol).
• The database includes diverse binding motifs, with a new classification scheme based on electrostatics, induction, dispersion, and mixtures.
• Critical error analysis shows high accuracy with average errors of ±0.1 kcal/mol.

Conclusions:

• NENCI-2021 is a valuable resource for testing and developing computational models.
• The database's comprehensive nature and high accuracy make it suitable for advancing force fields, DFT, and machine learning potentials.
• It addresses the need for diverse and high-quality data in computational chemistry.