Flash Photolysis Studies of Solute Triplets: an Anomalous Heavy Atom Effect of Xenon

Abstract

Flash photolysis studies show that in solutions of naphthalene in methylcyclohexane the apparent yield of the naphthalene triplet is enhanced ~6% by added krypton and ~50% by added xenon. The effect of xenon on the decay rate of the naphthalene triplet is anomalous; the decay rate decreases instead of increasing. This is attributed to complex formation between singlet excited naphthalene and xenon. We have also investigated the heavy atom effect in solutions of naphthalene in other solvents and in solutions of other solutes. It is anomalous in some of these solutions but to a lesser extent.