“…The pressure dependence can be shown to be negligible because of the large number of oscillators in the tert-butyl group. Now we have four experimental results which should be correlated via appropriate transition state models and/or the thermochemistry of the species involved: (a) Tsang's shock-tube study for the decomposition of 2,2,3,3-tetramethylbutane at 1100°K [9], log kl (sec-l) = 16.4 -67.8/8; (b) VLPP experiments [14] on the decomposition of TMB which confirm Tsang's parameters; (c) MGB [7a] and HB's [7b] study of the relative rate constant by using "known" thermochemistry of tert-butyl radicals around 400"K, log k, (M-',sec-') = -5-6; and (d) our present study at 700"K, log k, (M-'.sec-') c x 8.8 0.3. (Since the solvent effect on radical recombination is not known accurately, we did not include the electron spin resonance kinetic study [ 101.)…”