抄録
CO2 laser induced photodissociations of NH4+·nNH3 and of ND4+·nND3 were examined by a tandem mass spectrometer (TMS). Photodissociation took place for NH4+·nNH3 with n≥5. No photodissociation was observed for ND4+·nND3. It depended on the laser intensity, wave number, and cluster size. The maximum yield of NH4+·5NH3 dissociation was obtained at 1080 cm-1, and that of NH4+·7NH3 shifted to 1075 cm-1. Two molecules dissociation was observed in addition to one molecule dissociation. The yield of one molecule dissociation increased linearly with the laser intensity, indicating that the dissociation is a single photon process. Elementary processes which affect isotope effect in the dissociation are discussed.
