T-for-H substitution in methane: A hot-atom reaction with walden inversion?

Trajectory studies of the hot-atom reactions of tritium with methane have been made in which all six atoms Were tracked. Abstraction of H by T is a direct reaction. as expected. but T-for-H substitution is a concerted process involving: at least four atoms. There are indications that it may proceed with inversion of the methane structure.