title: Accurate ab initio thermal rate constants for reaction of O((3)P) with H2 and isotopic analogues.
abstract: Semiclassical transition state theory, in combination with high accuracy quantum chemistry, is used to compute thermal rate constants from first principles for the O((3)P) + H2 reaction and its isotopic counterparts. In the temperature regime of 298-3500 K (which spans 8 orders of magnitude for rate constants), our theoretical results are in excellent agreement (within 5-15%) with all available experimental data from 298 to 2500 K but are somewhat too low (from 15 to 35%) at higher temperatures. Several possible reasons that might cause the degradation at high temperatures are discussed. Vibrational state-selected rate constants and their correlations with normal thermal rate constant are derived and are given in the Supporting Information.
authors.affiliation: Department of Chemistry, The University of Texas at Austin , Mail Stop A5300 , Texas 78712-0165, United States.
authors.forename: Thanh Lam
authors.initials: TL
authors.lastname: Nguyen
authors.forename: John F
authors.initials: JF
authors.lastname: Stanton