State-resolved differential cross sections for the reaction D+H2→HD+H

Abstract

Differential cross sections for the reaction D+H2→HD+H were measured with a novel crossed molecular beam technique, in which a pulse of energetic D atoms is formed by 193 nm photolysis of D2S and crossed with a pulse of H2 at a variable intersection angle. Speed distributions of the product HD, measured by time-of-flight to a mass spectrometer detector, show clearly resolved peaks for v=0 and v=1 at center-of-mass scattering angles near 180°, for an initial relative kinetic energy of 0.95 eV. Analysis of the data by computer simulation of the experiment yields a v=0/v=1 population ratio of 5.1, and average rotational energies of 0.26 eV in V=0 and 0.11 eV in v=1.