ISSN:
1089-7690
Source:
AIP Digital Archive
Topics:
Physics
,
Chemistry and Pharmacology
Notes:
Starting from the formalism of collisional time-correlation functions, an expression is derived for the double differential cross section (with respect to scattering angles and final rotational energies) of molecules with a thermal distribution of initial rotational states, colliding with fast atoms. This expression is valid when the duration of the collision is short compared with the periods of internal motions of target molecules. The formulation leads to simple distributions in terms of error functions, which can be used to parametrize experimental results. The parameters in turn give the average rotational energy and its standard deviation for the final state. This procedure is followed to interpret recent experimental measurements of the final rotational distributions of CO and CO2 colliding with fast hydrogen atoms obtained from the photolysis of hydrides. For CO(v=1) and CO2(0001), in which the collisions are impulsive, the derived formula fits the experimental distribution very well. For CO(v=0), in which long-duration, complex-forming collisions play an important role, an additional statistical distribution can be introduced to satisfactorily explain the experimental results.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.456453
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