Generalized transition state theory and least-action tunneling calculations for the reaction rates of atomic hydrogen(deuterium) + molecular hydrogen(n = 1) .fwdarw. molecular hydrogen(hydrogen deuteride) + atomic hydrogen

Abstract

Improved canonical variational theory calculations are reported with least-action transmission coefficients for the reactions H + H/sub 2/(n=1) and D + H/sub 2/(n=1), where n denotes the vibrational quantum number, in both collinear and three-dimensional worlds and for three different potential surfaces. Where possible comparisons to accurate or more complete quantal calculations are made and very good agreement is found. For the three-dimensional reaction and the most accurate available potential energy surfaces comparisons to all available experimental determinations at 297-356 K are made; the experimental results are larger than the calculated rate constants by factors of (in chronological order) 26, 17, 60, 5, and 8. The disagreement is probably due in large part to the difficulty of experiments. 50 references, 1 figures, 7 tables.