Communication: efficient counterpoise corrections by a perturbative approach.

Area of Science:

• Computational Chemistry
• Quantum Chemistry
• Theoretical Chemistry

Background:

• Basis set superposition errors (BSSE) are significant in calculating interaction energies for weakly bound systems.
• Accurate estimation of counterpoise correction (CPC) is crucial for reliable interaction energy calculations.
• Conventional CPC methods can be computationally expensive.

Purpose of the Study:

• To investigate the efficacy of Hartree-Fock and density functional perturbative corrections for estimating CPC.
• To evaluate the performance of these perturbative approaches on the S22 dataset of weakly bound systems.
• To assess the computational speedup offered by perturbative CPC methods compared to conventional approaches.

Main Methods:

• Utilized Hartree-Fock and density functional perturbative corrections.
• Employed various popular basis sets for calculations.
• Tested the methods on the S22 set of weakly bound molecular systems.
• Compared computational times with conventional CPC calculation methods.

Main Results:

• Perturbative approaches successfully recovered over 95% of the counterpoise correction.
• The new methods demonstrated significant computational efficiency, being up to twelve times faster than conventional CPC calculations.
• The S22 dataset, known for large BSSE, was effectively analyzed.

Conclusions:

• Perturbative corrections offer a computationally attractive and accurate alternative for estimating CPC.
• These methods provide a valuable tool for researchers dealing with interaction energy calculations in weakly bound systems.
• The developed approach significantly reduces the computational cost associated with accurate BSSE correction.