March 27, 2022
Journal Article

Benchmark Electronic Structure Calculations for H3O+(H2O)(n), n=0-5, Clusters and Tests of an Existing 1,2,3-Body Potential Energy Surface with a New 4-Body Correction

Abstract

We report a revision of a previously developed many-body (up to 3-body inter- actions) CCSD(T)-based potential energy surface (PES) for the hydrated proton and its extension that incorporates a simple 4-body term for the hydronium-water-water-water interactions. The new PES is parametrized from and tested against new extensive benchmark CCSD(T) Complete Basis Set (CBS) estimates of the binding energies of H3O+(H2O)n clusters, n=0-5, which include all known to date low-lying energy isomers. We report the energetics, structures and harmonic frequencies of the hydronium-water clusters using the PES and compare them against the new benchmarks as well as other best available ab initio results. This critical comparison demonstrates the high accuracy of the new many-body hydronium-water PES.

Published: March 27, 2022

Citation

Heindel J., Q. Yu, J.M. Bowman, and S.S. Xantheas. 2018. Benchmark Electronic Structure Calculations for H3O+(H2O)(n), n=0-5, Clusters and Tests of an Existing 1,2,3-Body Potential Energy Surface with a New 4-Body Correction. Journal of Chemical Theory and Computation 14, no. 9:4553–4566. PNNL-SA-135496. doi:10.1021/acs.jctc.8b00598