STATISTICAL ADIABATIC CHANNEL CALCULATION OF ACCURATE LOW-TEMPERATURERATE CONSTANTS FOR THE RECOMBINATION OF OH RADICALS IN THEIR GROUND ROVIBRONIC STATE

Accurate low-energy capture cross sections and low-temperature capture rate constants for two OH radicals in their ground rovibronic states X (2) Pi(3/2)(v = 0, j = 3/2) were calculated within the statistical a diabatic channel approach, The rate constants calculated in first orde r provide a good approximation to the true rate constant below 4 K. Th e rate constants calculated in second order provide a correction of ab out 25% to the first order rate constant at 20 K and indicate an only weak temperature dependence at T>20 K. At higher temperatures deviatio n of the potential from long-range electrostatic interaction have to b e accounted for. (C) 1995 American Institute of Physics.