Rotational Polarization of Product Molecules: Crossed Laser-Molecular Beam Studies of Ca^* + HF and Ca + F₂

Quantitative results have been obtained for the alignment, due to chemical reactions under single collision conditions, in CaF(X) product molecules using the technique of laser-induced fluorescence (LIF). We find that the anisotropic distribution of angular momenta is of the form 1 + A₂P₂(cosv), where the alignment appears to be large (A₂ = - 1.82 ± 0.06) for Ca^* + HF → CaF + H, while for Ca + F₂ → CaF + F a considerably smaller alignment (A₂ = -0.14 ± 0.09) is measured and discussed.