Dynamics of the O(3P) + CH4→OH + CH3Reaction Is Similar To That of a Triatomic Reaction.

The O(3P) + CH4reaction has beeninvestigatedusing the quasi-classical trajectory (QCT) method and an abinitiopseudotriatomic potential energy surface (PES). Thishas been mainly motivated by very recent experiments which supportthe reliability of the triatomic modeling even at high collision energy(⟨Ecol⟩ = 64 kcal mol–1). The QCT results agree rather well with the experiments(translational and angular distributions of products); i.e., the ab initiopseudotriatomic modeling “captures”the essence of the reaction dynamics, although the PES was not optimizedfor high Ecol. Furthermore, similar experimentson the O(3P) + CD4reaction at moderate Ecol(12.49 kcal mol–1) havealso been of a large interest here and, under these softer reactionconditions, the QCT method leads to results which are almost in quantitativeagreement with experiments. The utility of the ab initiopseudotriatomic modeling has also been recognized for other analogoussystems (X + CH4) but with very different PESs. [ABSTRACT FROM AUTHOR]