The dynamical Renner--Teller effect. II. Rotationally inelastic scattering of NCO( tilde X sup 2. Pi. ,00 sup 1 0)+He

Journal Article · Wed Jul 15 04:00:00 EDT 1992 · Journal of Chemical Physics; (United States)

DOI:https://doi.org/10.1063/1.463200· OSTI ID:7105601

Macdonald, R G; Liu, K ^[1]

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1. Chemistry Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States)

State-resolved integral cross sections for the inelastic scattering of the Hund's case (a) radical NCO({ital {tilde X}} {sup 2}{Pi}) by He have been measured in a crossed-beam apparatus. Two different types of measurements are reported: (1) state-resolved integral cross sections at fixed collision energies from 0.94--3.05 kcal mol{sup {minus}1} and (2) the collision energy dependence of state-specific product states for both {sup 2}{Pi}{sub 3/2} and {sup 2}{Pi}{sub 1/2} spin--orbit states of NCO({ital {tilde X}} {sup 2}{Pi},00{sup 1}0). As in a preliminary account of this work for {ital E}{sub 0}=3.74 kcal mol{sup {minus}1} (J. Phys. Chem. {bold 91}, 9630 (1991)), herein referred to as part I, dramatically different rotational level distributions were found for spin--orbit conserving or changing collisions. It is argued that this behavior and many other observations on this system are generic to the inelastic scattering of Hund's case (a) {sup 2}{Pi} radicals. A conceptual framework to understand these results is elucidated in detail. The direct connection between the experimental observables and the Hund's case classification is made for the inelastic scattering of radicals. This connection can be viewed as a dynamical consequence of the Renner--Teller effect.

• Research Organization: Argonne National Laboratory (ANL), Argonne, IL
• DOE Contract Number: W-31109-ENG-38
• OSTI ID: 7105601
• Journal Information: Journal of Chemical Physics; (United States), Journal Name: Journal of Chemical Physics; (United States) Vol. 97:2; ISSN JCPSA; ISSN 0021-9606
• Country of Publication: United States
• Language: English

Related Subjects

664300* -- Atomic & Molecular Physics-- Collision Phenomena-- (1992-)
74 ATOMIC AND MOLECULAR PHYSICS
ATOM COLLISIONS
ATOM-MOLECULE COLLISIONS
BEAMS
CARBONYL RADICALS
COLLIDING BEAMS
COLLISIONS
COUPLING
CROSS SECTIONS
ELEMENTS
ENERGY
ENERGY DEPENDENCE
ENERGY LEVELS
EXCITED STATES
FLUIDS
GASES
HELIUM
INELASTIC SCATTERING
INTEGRAL CROSS SECTIONS
INTERMEDIATE COUPLING
L-S COUPLING
MOLECULE COLLISIONS
NONMETALS
POTENTIAL ENERGY
RADICALS
RARE GASES
RESOLUTION
ROTATIONAL STATES
SCATTERING