1. For reviews see P. J. Robinson and K. A. Holbrook, Unlmolecular Reactions, Wiley, New York (1972),
2. W. Forst, Theory of Unlmolecular Reactions, Academic Press, New York (1973).
3. S.A. Rice in Excited States, Ed. E. C. Lim, Academic Press, New York (1975), Vol. 2, p. 111.
4. For example, the inference that vibrational relaxation on the ground electronic surface of HCCCl is slow, suggested by K. Evans, D. Heller, S.A. Rice and R. Scheps, J. Chem. Soc. Faraday Trans. 2 69, 856 (1973)
5. is not in agreement with trajectory calculations by W. L. Hase, J. Chem. Phys. 66, 1523 (1977). I believe the trajectory calculations should be accepted as more reliable. Presumably the bottleneck in the photodissociation of HCCCl in crossing to the ground electronic state from the prepared excited state.