Mass and orientation effects in dissociative collisions between rare gas atoms and alkali halide molecules

Journal Article · Sat Nov 01 00:00:00 EST 1980 · J. Chem. Phys.; (United States)

DOI:https://doi.org/10.1063/1.440683· OSTI ID:7053729

Tully, F P; Cheung, N H; Haberland, H; Lee, Y T

The collision induced dissociation of alkali halide molecules to ion pairs upon impact with hyperthermal rare gas atoms has been investigated using the crossed molecular beam method. Relative total cross sections for the dissociation of CsI, CsBr, RbI, and KI to ion pairs upon collision with xenon and krypton have been measured over a relative collision energy range from threshold to 10 and 8 eV, respectively. In addition, complete angular and energy distributions of both dissociated ions from Xe+CsI, CsBr, and RbI collisions and from Kr+CsI and CsBr collisions have been obtained at several collision energies within the above energy range. Mass, collision orientation, and energy dependence effects observed throughout this work define two limiting case dissociation mechanisms for the Xe(Kr)+MX..-->..Xe(Kr)+M/sup +/+X/sup -/ processes. The dominant dissociation configuration consists of the rare gas atom incident on the light atom end of the alkali halide molecule in a near collinear collision. The less preferred dissociation mechanism results when the rare gas atom is incident in a near collinear configuration on the heavy atom end of the alkali halide molecule. Experimental measurements of the percentage of energy transfer from the relative kinetic energy between Xe(Kr) and MX to the relative motion of M/sup +/--X/sup -/ range as high as 95%; these percentage energy transfers correlate well with the predictions of an impulsive collision model. Three-dimensional classical trajectory calculations using realistic interaction potentials have been performed and they verify the dynamical interpretation suggested by the experiments.

• Research Organization: The James Franck Institute and Department of Chemistry, The University of Chicago, Chicago, Illinois 60637
• OSTI ID: 7053729
• Journal Information: J. Chem. Phys.; (United States), Vol. 73:9
• Country of Publication: United States
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS
CESIUM BROMIDES
ATOM-MOLECULE COLLISIONS
CESIUM IODIDES
KRYPTON
POTASSIUM IODIDES
RUBIDIUM IODIDES
XENON
COLLIDING BEAMS
DISSOCIATION
ENERGY SPECTRA
EXPERIMENTAL DATA
ION PAIRS
MOLECULAR BEAMS
TOTAL CROSS SECTIONS
ALKALI METAL COMPOUNDS
ATOM COLLISIONS
BEAMS
BROMIDES
BROMINE COMPOUNDS
CESIUM COMPOUNDS
COLLISIONS
CROSS SECTIONS
DATA
ELEMENTS
FLUIDS
GASES
HALIDES
HALOGEN COMPOUNDS
INFORMATION
INORGANIC PHOSPHORS
IODIDES
IODINE COMPOUNDS
MOLECULE COLLISIONS
NONMETALS
NUMERICAL DATA
PHOSPHORS
POTASSIUM COMPOUNDS
RARE GASES
RUBIDIUM COMPOUNDS
SPECTRA
640304* - Atomic
Molecular & Chemical Physics- Collision Phenomena