Journal of Physical Chemistry A, Vol.112, No.39, 9266-9268, 2008
Corroboration of theory for H+D-2 -> D+HD (v'=3, j'=0) reactive scattering dynamics
The differential cross section (DCS) for the reaction H + D-2 -> D + HD (v' = 3, j' = 0) exhibits particularly rich dynamics; in addition to the expected direct recoil backscattering feature, a surprising time-delayed forward scattering feature appears that has been attributed to glory scattering arising from nearside and farside interference. This fact leads to a complex DCS that depends strongly on the collision energy. Its accurate calculation requires a fully quantum mechanical (QM) treatment. We report improved measurements of this DCS over the collision energy range 1.55 <= E-coll <= 1.82 eV. Previous measurements using the core extraction method, while generally in agreement with theory, lacked sufficient resolution to capture all of the noteworthy behavior of the system; in the present work, we use ion imaging to observe many previously unresolved features of the DCS, particularly in the forward-scattered region. Agreement with QM calculations is found at all collision energies, reconciling an earlier discrepancy between experiment and theory near E-coll = 1.54 eV.