PHOTODISSOCIATION OF MGC60-TRAP( COMPLEXES GENERATED AND STORED IN A LINEAR ION)

This Letter presents a general technique for the determination of abso lute photodissociation cross-sections of ionic molecular complexes in the gas phase. Experiments on MgC60+ complexes were used to demonstrat e the effectiveness of this approach. The complexes were generated col lisionally inside a linear ion trap, and stored for periods of 30 s or longer during which laser induced photodissociation measurements were carried out. The dissociation rates were determined using either a ma ss spectrometric or a fluorescence technique, and were found to have a linear dependence on incident laser powers up to 50 mW(similar to 300 W/cm(2) intensity). The total photodissociation cross-sections increa se from 10(-18) to 10(-16) cm(2) for photon energies ranging from 1.96 to 4.46 eV.