THE DYNAMICS OF HYDROGEN ABSTRACTION REACTIONS - CROSSED-BEAM REACTION CL-C5H12-]C5H11+HCL(N)

We present a crossed molecular beam study of the dynamics of the metat hesis reaction Cl + n-C5H12-->HCl+C5H11 at a collision energy of 16.8 kcal/mol. The experiments were conducted on the Chemical Dynamics Beam line at the Advanced Light Source, using tunable undulator radiation t o effect soft ionization of the pentyl radical product. Laboratory ang ular distributions and time-of-flight spectra at many laboratory angle s were used to obtain the center-of-mass translational energy and angu lar distributions. These distributions were found to be strongly coupl ed, with the forward scattered pentyl radical formed extremely cold, w hile the backscattered radicals were formed leaving nearly 15 kcal/mol in internal energy in the products. These results are contrasted with recent studies on the analogous reaction with propane, suggesting in this case direct involvement of the carbon skeleton in the collision p rocess. [S0021-9606(98)02437-4].