Threshold behavior of collisional ionization processes

Crossed molecular-beam studies have been conducted for collisional-ionization (CI) reactions: Cs + XY → Cs+ + XY-, (CI) and collision-induced dissociation (CID) reactions: Cs + XY → Cs+ + X + Y-, (CID) where X and Y may be atoms or molecules. The cross section for the production of Cs+ was measured. The center-of-mass (c.m.) threshold energies (E0) for these endoergic reactors, assuming ground-state reactants and products, are E0(CI) = I(Cs) - A(XY- and E0(CID) = I(Cs) + D0(XY) - A(Y- = I(Cs) + D0(XY-) - A(XY-), where A, D0, and I are the electron affinity, bond-dissociation energy, and ionization potential, respectively. Appropriate A and D0 values for the target molecules were deduced from these relations with the measuring E0 and known I(Cs). (Diss. Abstr. Int., B)