Knowledge Bank

Radical cations of naphthalene, anthracene, and pyrene have been formed by electron bombardment of a vapor phase mixture of the PAH parent, $CCl4$ and argon and subsequently trapped in a matrix at 12K. New infrared bands in all three cations have been correlated with prominent visible bands know to be due to the radical cation. Comparison of the observed frequencies to recent ab initio calculations on these cations show excellent agreement. The role of $CCl4$ as an ionization enhancer and matrix charge stabilizer will be discussed.