Comparison of experimental time-of-flight spectra of the HF products from the F+H-2 reaction with exact quantum mechanical calculations

摘要

High resolution HF product time-of-flight spectra measured for the reactive scattering of F atoms from n-H-2(p-H-2) molecules at collision energies between 69 and 81 meV are compared with exact coupled-channel quantum mechanical calculations based on the Stark-Werner ab initio ground state potential energy surface. Excellent agreement between the experimental and computed rotational distributions is found for the HF product vibrational states v'=1 and v'=2. For the v'=3 vibrational state the agreement, however, is less satisfactory, especially for the reaction with p-H-2. The results for v'=1 and v'=2 confirm that the reaction dynamics for these product states is accurately described by the ground electronic state 1 (2)A' potential energy surface. The deviations for HF(v'=3,j(')>= 2) are attributed to an enhancement of the reaction resulting from the 25% fraction of excited (P-2(1/2)) fluorine atoms in the reactant beam. (C) 2005 American Institute of Physics.