10.1021/jp0020541.s001 Baoshan Wang Baoshan Wang Hua Hou Hua Hou Yueshu Gu Yueshu Gu Theoretical Study of the Reaction of Atomic Hydrogen with Acetonitrile American Chemical Society 2000 G 3 barrier height ZPE B 3LYP level energy surface TST hydrogen abstraction path HCN RRKM G 3 level CH 2 CN 2000-12-12 00:00:00 Journal contribution https://acs.figshare.com/articles/journal_contribution/Theoretical_Study_of_the_Reaction_of_Atomic_Hydrogen_with_Acetonitrile/3721530 The reaction of atomic hydrogen with acetonitrile has been studied using the B3LYP and Gaussian-3 (G3) methods. The geometries and vibrational frequencies of various stationary points on the potential energy surface were calculated at the B3LYP level with the 6-311G(d,p) and 6-311++G(2d,2p) basis sets. The energetics were refined at the G3 level. The G3 barrier height has been calibrated using a test set including 39 well-established reactions. It is believed that the present potential energy surface is reliable within chemical accuracy. The title reaction starts in four manners, namely direct hydrogen abstraction, C-addition, N-addition, and substitution. The corresponding barrier heights (including ZPE corrections) are 12.0, 7.6, 9.6, and 44.7 kcal/mol, respectively. The kinetics of the reaction were studied using the TST and multichannel RRKM methodologies over the temperature range 300∼3000 K, and were compared with the earlier experimental data. At lower temperatures, the C-addition step is the most feasible channel, and the major products are CH<sub>3</sub> and HCN at lower pressures. At higher temperatures, the direct hydrogen abstraction path leading to H<sub>2</sub> and CH<sub>2</sub>CN is apparently dominant.