Photophysics and photochemistry of I2 (D, D′) in rare gas clusters

Abstract

Abstract We report the resolved fluorescence spectra of I 2 , clustered with Ar, Kr and Xe and excited at 193 nm to the D state of the first ion-pair manifold. In Ar and Kr clusters, a broad, featureless emission band is seen, which shifts to lower energies as the cluster size increases. In Xe clusters, this band is not observed; there is very efficient quenching of all emission. Under some expansion conditions, XeI ∗ excimer emission is observed with a two-photon dependence on the intensity of the 193 nm excitation laser. These results are all explained by a model in which excitation of I 2 into the ion-pair manifold is followed by a harpooning-type electron transfer and formation of an excited charge transfer complex between I 2 and a rare gas atom.