Dynamic range matrix assisted laser

Fig. 13.1 Relaxation in the X X (ground electronic state) and A n (excite electronic state) vibrational manifolds of the CN radical in Ne host matrix at T = 4 K, following excitation into the third vibrational level ofthe If state. Populations in individual vibrational levels in both electronic states are monitored independently by fluorescence (for the If state) and by laser induced fluorescence (for the X state). The preferred relaxation pathway for energies above the origin of the Tt state is found to be medium assisted internal conversion as indicated by arrows in the left panel. The right panel shows the dynamics of population and subsequent decays of the vibrational levels 6, 5, 4, and 3 of the ground X state. Levels 6 and 5 relax much faster (lifetimes in the order of 1-3 /xs) than levels 4 and 3 (lifetimes in the ms range). For the latter the internal conversion-assisted pathway is closed as seen in the state diagram on the left, so these long lifetimes correspond to pure vibrational transitions. (From V. E. Bondybey and A. Nitzan, Phys. Rev. Lett. 38, 889 (1977).)...

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