title: Structural Distortions Accompanying Noncovalent Interactions: Methane-Water, the Simplest C-H Hydrogen Bond.
abstract: Neglect of fragment structural distortions resulting from noncovalent interactions is a common practice when examining a potential energy surface (PES). Herein, we make quantitative predictions concerning the magnitude of such distortions in the methane-water system. Coupled cluster methods up to perturbative quadruples [CCSDT(Q)] were used in the structural optimizations to the complete basis set limit (using up to cc-pV6Z basis sets). Our results show that the interaction energy differences between the fully optimized and nonoptimized structures are on the order of 0.02 kcal mol-1. These findings imply that scanning the PES of a very weakly bound noncovalent system, while neglecting intramolecular distortions, is a reasonable approximation for points other than the minima.
authors.affiliation: Instituto de Física, Universidad Nacional Autónoma de México , Ciudad de México 04510, México.|Center for Computational Quantum Chemistry, Department of Chemistry, The University of Georgia , Athens, Georgia 30602-2556, United States.
authors.forename: Herzain I
authors.initials: HI
authors.lastname: Rivera-Arrieta
authors.affiliation: Center for Computational Quantum Chemistry, Department of Chemistry, The University of Georgia , Athens, Georgia 30602-2556, United States.
authors.forename: Justin M
authors.identifier: http://orcid.org/0000-0003-3659-0711
authors.initials: JM
authors.lastname: Turney
authors.affiliation: Center for Computational Quantum Chemistry, Department of Chemistry, The University of Georgia , Athens, Georgia 30602-2556, United States.
authors.forename: Henry F
authors.identifier: http://orcid.org/0000-0003-0252-2083
authors.initials: HF
authors.lastname: Schaefer