Mode-specific quantum dynamics and kinetics of the hydrogen abstraction reaction OH + H2O → H2O + OH. Issue 43 (24th October 2019)

• Record Type: Journal Article
• Authors: Zheng, Rui; Zhu, Yongfa; Song, Hongwei
• Is Part Of: Physical chemistry chemical physics. Volume 21:Issue 43(2019)
• Page Start: 24054
• Page End: 24060
• Publication Date: 2019-10-24
• Subjects: Chemistry, Physical and theoretical -- Periodicals; 541.3
• DOI: 10.1039/c9cp04721b
• Languages: English
• ISSNs: 1463-9076

Abstract

Abstract : The synergistic effect between the reactant stretching and bending modes on promoting the reaction. Abstract : Hydrogen abstraction processes are prevalent in a wide range of chemically active environments. In this work, the prototypical hydrogen exchange reaction OH + H2 O → H2 O + OH is investigated on an accurate ab initio based potential energy surface using an initial state-selected time-dependent wave packet method. Exciting either the symmetric stretching mode or the antisymmetric stretching mode of the reactant H2 O promotes the reaction more than exciting the bending mode. The vibrational energy initially deposited in H2 O is more efficient than the translational energy in promoting the reaction. There exists a remarkable synergistic effect between the stretching mode and the bending mode as the efficacy for the combination band excitation is larger than the sum of individual excitations. The mode-specific dynamics is partially rationalized by the sudden vector projection model. Besides, the mode-specific rate constants apparently exhibit a strong non-Arrhenius behavior at low and moderate temperatures.