Exciplex formation reaction in benzaldehyde-1,4-dimethoxybenzene clusters

It was demonstrated that the intracluster exciplex formation reaction occur s by the laser excitation of benzaldehyde (BA) in BA/1,4-dimethoxybenzene ( DMB) clusters. The exciplex formation was inferred from spectral broadening , the red-shifted emission spectrum from BA monomer fluorescence and the li near laser power dependence of the emission intensity. The exciplex emissio n appears in the region from 400 to 600 nm and its lifetime was estimated t o be less than 20 ns which is remarkably shorter than the fluorescence life time of the BA monomer (> 1 mu s). Exciplex formation dynamics in the clust ers is discussed on the basis of the fluorescence excitation spectrum of th e exciplex and the fluorescence lifetime. (C) 2000 Elsevier Science B.V. Al l rights reserved.