Impact of Post-CCSD (T) Corrections on Reaction Energetics and Rate Constants of OH˙+HCl Reaction
Subhasish Mallick and Pradeep Kumar
Department of Chemistry, MNIT Jaipur, Jaipur, 302017,India
High level ab initio calculations have been performed to predict the reaction energy and barrier height for OH˙+HCl reaction. After including the effect of full quadratic excitations at coupled cluster level, in addition to core, relativistic, spin-orbit and diagonal Born-Oppenheimer corrections, the values of reaction energy and barrier height were found to be -15.29 and 2.38 kcal mol−1 , respectively. Employing this reaction energy and barrier height, we used variational transition state theory in conjunction with small curvature tunneling to calculate the rate constants within a temperature range from 138 to 900 K. The calculated rate constants were found to be in good agreement with the available experimental results throughout the whole temperature range.