VIBRATIONAL PREDISSOCIATION IN S1 INDOLE VANDERWAALS CLUSTERS

The excited state dynamics of the indole(Ar)1, indole(d1) (Ar)1, indole(Ar)2, and indole(CH4)1 van der Waals clusters have been investigated in a free jet expansion. Excited state vibrational frequencies were determined using multiphoton ionization and fluorescence excitation spectroscopy. Time resolved emission spectroscopic techniques were used to determine vibrational predissociation rates and product state distributions. All of the clusters were found to predissociate when excited with sufficient vibrational energy in the S1 state. The predissociation dynamics were found to be consistent with a serial model in which energy transfer from the indole skeletal modes to the van der Waals modes precedes the dissociation step. The density of van der Waals vibrational states was found to be the most important factor in determining the predissociation dynamics.