State-to-state dynamics of H+HX collisions. II. The H+HX. -->. HX/sup dagger/+H (X = Cl,Br,I) reactive exchange and inelastic collisions at 1. 6 eV collision energy

Journal Article · Mon May 01 04:00:00 EDT 1989 · J. Chem. Phys.; (United States)

OSTI ID:6456452

Aker, P M; Germann, G J; Tabor, K D; Valentini, J J

We report measurement of product state distributions for the rotationally and/or vibrationally excited HX formed in collisions of translationally hot H atoms with HX (X = Cl, Br, and I) at 1.6 eV collision energy. The product state distributions are probed after only one collision of the fast H atom, using coherent anti-Stokes Raman scattering spectroscopy. Whether proceeding by inelastic collisions or reactive exchange, the transfer of translational energy to vibrational and rotational energy is quite inefficient in H+HX collisions at 1.6 eV. For all three hydrogen halides only 2--3% of the initial translational energy appears as HX vibration. For H+HCl only 6% of the initial energy is converted to HCl rotational energy, while for H+HBr and H+HI, this percentage is twice as large, 11--12%, but still small. The indistinguishability of the two H atoms involved makes it impossible to distinguish reactive exchange from inelastic energy transfer in these H+HX collisions. However, the difference in rotational energy partitioning for H+HBr and H+HI as compared with H+HCl, suggests that reactive exchange is dominant in the former and inelastic energy transfer dominates in the latter. The total cross sections for the combined energy transfer/reactive exchange do not change much with the identity of X, being 13 +- 3, 11 +- 2, and 11 +- 2 A/sup 2/, for H+HCl, H+HBr, and H+HI, respectively.

• Research Organization: Department of Chemistry, University of California, Irvine, California 92717
• OSTI ID: 6456452
• Journal Information: J. Chem. Phys.; (United States), Journal Name: J. Chem. Phys.; (United States) Vol. 90:9; ISSN JCPSA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201 -- Chemical & Physicochemical Properties
640304* -- Atomic
Molecular & Chemical Physics-- Collision Phenomena
74 ATOMIC AND MOLECULAR PHYSICS
ATOM COLLISIONS
ATOM-MOLECULE COLLISIONS
CHEMICAL REACTIONS
COLLISIONS
CROSS SECTIONS
ELEMENTS
ENERGY LEVELS
ENERGY RANGE
ENERGY TRANSFER
EV RANGE
EV RANGE 01-10
EXCITED STATES
HALOGEN COMPOUNDS
HYDRIODIC ACID
HYDROBROMIC ACID
HYDROCHLORIC ACID
HYDROGEN
HYDROGEN COMPOUNDS
INORGANIC ACIDS
IODINE COMPOUNDS
LASER SPECTROSCOPY
MOLECULE COLLISIONS
NONLINEAR OPTICS
NONMETALS
OPTICS
RAMAN SPECTROSCOPY
ROTATIONAL STATES
SPECTROSCOPY
VIBRATIONAL STATES