ULTRAFAST INTRACLUSTER FRAGMENTATION IN HIGHLY EXCITED BENZENE-AMMONIA COMPLEXES

The dynamics of intracluster fragmentation in highly excited benzene(N H3)(n) heteroclusters has been studied and compared with the ultrafast process of internal conversion. In pump-probe experiments with 170 fs laser pulses the clusters were excited to 6.2 eV and probed with 3.1 eV photons. The time constants for the dominant process of internal co nversion as well as the parallel channel of fragmentation by NH2 loss have been determined by fitting the measured time dependence with corr esponding theoretical curves. No significant differences were obtained comparing the internal conversion in benzene(NH3)(n) and benzene(ND3) (n) complexes.