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

It was demonstrated that the intracluster exciplex formation reaction occurs 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 linear laser power dependence of the emission intensity. The exciplex emission appears in the region from 400 to 600 nm and its lifetime was estimated to be less than 20 ns which is remarkably shorter than the fluorescence lifetime of the BA monomer (>1 μs). Exciplex formation dynamics in the clusters is discussed on the basis of the fluorescence excitation spectrum of the exciplex and the fluorescence lifetime.