MICROCANONICAL VARIATIONAL THEORY OF RADICAL RECOMBINATION BY INVERSION OF INTERPOLATED PARTITION-FUNCTION .2. CX3 + O2 (X = H, F, CL)

The title theory (MVIPF) has been applied to the recombinations of O2 with the radicals CH3, CF3, CF2Cl, CFCl2 and CCl3 and compared, with generally good results, to experimental data which are available for all radicals but one (CF2Cl). In particular, MVIPF, which is based on minimum information and uses an adjustable parameter (c) in a Gaussian-type switching function, correctly reproduces the fact that the recombination CH3 + O2 has a positive temperature coefficient, while all the other radical recombinations have a negative temperature coefficient. Consolidated results by MVIPF for the nine recombination reactions for which experimental data are available (the title reactions, plus CH3 + H, CH3 + CH3, CH2Cl + CH2Cl, CHCl2 + CCl3, CCl3 + CCl3), yield a linear relation for a function of the logarithm of c, which in principle allows one to predict a recombination rate constant in a series of similar reactions within a factor of two.