Fluorescence of protonated pyrene and coronene in neon matrices

Please cite this article in press as: I. Garkusha e Fluorescence spectra of protonated pyrene and coronene in solid neon have been observed. Laser excitation of the Sn S0 transitions of the cations results in an extended, vibrationally-resolved S1 ? S0 fluorescence with onset at 487.8 and 695.4 nm for protonated pyrene and coronene, respectively. Vibrational assignment of the spectra has been made on the basis of the calculated frequencies of normal modes in the ground electronic state. The astrophysical relevance of the frequencies inferred for these protonated cations is discussed. 2012 Elsevier B.V. All rights reserved.