The elimination of HF from vibrationally excited fluoroethanes. The decomposition of 1,1,1‐trifluoroethane‐d0 and d3

The vibrationally excited molecules CF3CH and CF3CD have been synthesized by radical combination (produced by ketone photolysis), and HF and DF elimination from them studied as a function of temperature and pressure. Using RRK theory many calculations have recently been made of critical energies for the decomposition of "hot" fluoroethane molecules. Taking CF3CH as an example, it is concluded that the empiricism involved in such calculations renders results of doubtful significance. The non‐equilibrium kinetic isotope effect is kH/kD = 3.1 at 470°K. Arrhenius parameters are also presented for radical abstraction reactions from the ketone source molecules.