STATE-SELECTED PHOTODISSOCIATION OF THE B1-PI-U STATE OF K2 BY ALL-OPTICAL TRIPLE RESONANCE SPECTROSCOPY

The state-selected photodissociation of K2 has been studied by all-optical triple resonance spectroscopy using three single-mode CW dye lasers. In particular, the positions and widths of transitions K2(X1-SIGMA-g+, upsilon" = 17, J") + h-nu --> K2* (B1-PI-u, upsilon' = 43, J' = 10-43) corresponding to excitation of quasibound resonances in the photodissociation of K2 have been studied. For low J' (10-28) the photodissociation was indirectly observed by studying the molecular fluorescence K2*(B1-PI-u, upsilon' = 43, J') --> K2(X1-SIGMA-g+, upsilon" = 60, J") + h-nu-m, while for high J' (20-43), the photodissociation was directly observed by studying the K*(4p 2P3/2) atomic fluorescence K2*(B1-PI-u, upsilon' = 43, J') --> K*(4p 2P3/2) + K and K*(4p 2P3/2) --> K (4s 2S1/2) + h-nu-a. Predictions of both decay processes using a B1-PI-u potential curve based on the work of Heinze and Engelke (J. Chem. Phys. 1988, 89, 42) agree well with observations.