Effect of Alkylammonium Ions on the Photochemical Behaviors of γ-Stilbazolium Aggregates in Clay Interlayers

Effect of alkylammonium ions (Cn+) has been studied on the clusterization and photochemical behaviors of γ-stilbazolium (4-(2-phenylvinyl)pyridinium) ion (1) adsorbed on clay interlayers. The aggregates of 1 were shown to be dissociated by the coadsorption of Cn+ with molecular length longer than that of 1. The major photoreaction was changed from cyclodimerization to E–Z isomerization on coadsorbing Cn+’s longer than 1. The efficient excimer emission from intercalated 1 was dramatically reduced by coadsorbing alkylammonium ions. The resulting concentration dependence of excimer emission intensity is nicely simulated by a Monte Carlo method for two-dimensional lattice site models.