An exploratory study of reactant vibrational effects in CH3 + H2 and its isotopic variants

Abstract

The effects of reactant vibrational, fine structure, and collision energy on the reactions of OCS+ with C2H2: Complementary studies of reactions in the [C2H2+OCS]+ system J. Chem. Phys. 94, 6459 (1991); 10.1063/1.460275The bendingcorrectedrotatinglinearmodel calculations of the rate constants for the H+H2 reaction and its isotopic variants at low temperatures: The effect of van der Waals well An empirically calibrated potential energy surface, obtained previously [I. Chem. Phys. 61, 21 (1974)], was used in a trajectory study of the effect of reactant energy partitioning on cross sectionfor CH] + H2 -> CH. + H. Artificial variations in the barrier position, and artificial and naturally occuring changes in the H masses, were also made. For natural CH) + H 2 , H2 vibration enhances and CH 3 out-of-plane bending depresses the cross section, at constant (25 kcal) translational energy of approach. The isotope substitution and barrier position effects are more complex and not predictable from triatomic A + BC generalizations. The relationship of these results to experimental ones is discussed.

Classical trajectory studies of the reaction CH4+H→CH3+H2

“…4 Classical trajectory calculations have not been performed hitherto on this surface, although there are a number of such studies on more primitive potentials. [5][6][7][8][9] These previous results will serve as guidelines for the present work.…”

“…In later papers Valencich and Bunker 7,8 reported a six-atom calculation with all hydrogenic atoms treated equivalently. The potential function proposed by Valencich and Bunker and later modified 9 was a purely empirical form fit to experiment. At approximately the same time Raff proposed a surface 10 that was based upon semiempirical INDO calculations and ab initio quantum calculations.…”

H + CD4 Abstraction Reaction Dynamics: Excitation Function and Angular Distributions

“…As a result it has long served as a benchmark for theoretical studies of atom plus polyatomic molecule reactions. 11,[15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31] Much of this work has been concerned with determination of stationary point properties and the rate constants, although occasionally there has been work on the state-resolved dynamics. Many potential energy surfaces (PES) have been developed.…”

Crossed molecular beam studies of the reactions of methyl radicals with iodoalkanes

“…Finally, Chapman and Bunker [30] have found from trajectory calculations that depositing energy in v 2 actually decreases the cross section for H atom transfer in CH 3 + H 2 .…”