Molecular Beam Study of Steric Effects in the Reaction K + HF (v = 1, j = 2) -> KF + H

Article abstract of DOI:10.1021/j100305a012

HF molecules were optically aligned by use of linearly polarized infrared radiation generated by a color center laser tuned to the R₁(l) line of HF.The state-specific integral cross section of the reaction K + HF (v = 1, j = 2) -> KF + H was measured for the two different preparations of the approach geometry which result when the plane of polarization is positioned either parallel (?_<*>) or perpendicular (?_<*>) to the most probable relative velocity of the reagents.At a translational energy of E_tr = 0.46 eV the resulting relative difference of the cross sections (?_<*> - ?_<*>)/?<*>(?<*> = 1/2(?_<*> + ?_<*>)) amounts to 17 +/- 5percent.This steric effect decreases with rising E_tr and reaches zero near 1.2 eV.The data strongly suggest that the reaction occurs via a collinear transition state.