Damping of total differential cross sections: Observations and empirical anisotropic potentials for HeC/sub 2/H/sub 2/ and HeOCS
Differential cross section (DCS) measurements are reported for scattering of a He atomic beam by crossed beams of Ar, C/sub 2/H/sub 2/, CO/sub 2/, and OCS. Relative to the HeAr diffractive structure, the HeC/sub 2/H/sub 2/ DCS is moderately damped at small scattering angles and severely damped at large scattering angles; the HeCO/sub 2/ and HeOCS DCS's are severely damped for all scattering angles. This damping directly reflects increasing anisotropy of the scattering partner from Ar (none) to C/sub 2/H/sub 2/ (moderate) to CO/sub 2/ and OCS (strong). Even though the present data do not resolve elastic from inelastic contributions, the HeCO/sub 2/ results are consistent with partially resolved inelastic DCS measurements (U. Buck, H. Meyer, M. Tolle, and R. Schinke, Chem. Phys. 104, 345 (1986)) and therefore complement them. Consequently the data are used to obtain empirical anisotropic intermolecular potentials for HeC/sub 2/H/sub 2/ and HeOCS within the infinite-order-sudden approximation. These reproduce the total (unresolved elastic +inelastic) DCS measurements very well, even though the angular asymmetry of OCS is ignored in the analysis.
- Research Organization:
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
- OSTI ID:
- 6494781
- Journal Information:
- J. Chem. Phys.; (United States), Vol. 87:1
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
ACETYLENE
ATOM-MOLECULE COLLISIONS
ARGON
ATOM-ATOM COLLISIONS
INTERMOLECULAR FORCES
CARBON DIOXIDE
CARBON OXYSULFIDE
HELIUM
ATOMIC BEAMS
DAMPING
DIFFERENTIAL CROSS SECTIONS
MOLECULAR BEAMS
POTENTIALS
ALKYNES
ATOM COLLISIONS
BEAMS
CARBON COMPOUNDS
CARBON OXIDES
CHALCOGENIDES
COLLISIONS
CROSS SECTIONS
ELEMENTS
FLUIDS
GASES
HYDROCARBONS
MOLECULE COLLISIONS
NONMETALS
ORGANIC COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
RARE GASES
SULFUR COMPOUNDS
640304* - Atomic
Molecular & Chemical Physics- Collision Phenomena