| Abstrakt: |
Multiple pulsed-laser frequencies are used to extract the excitation spectra ofDn←D0transitions (n> 1) of the 1- and 2-naphthylmethyl, 1-phenylpropargyl and 9-anthracenylmethyl radicals. Bands are, respectively, observed at 27993, 27478, 32437 and 25063 cm−1, with respective widths (at half maximum) of 292, 290, 149 and 326 cm−1. On the basis of comparison withab initiovertical excitation energies, the transitions for 2-naphthylmethyl, 1-phenylpropargyl and 9-anthracenylmethyl radical are assigned asD3←D0. The observed transition of 1-naphthylmethyl is ambiguously either or bothD3←D0andD4←D0. From the wide Lorentzian profiles observed, lifetimes of a few tens of fs are inferred, the spectral widths precluding this class of molecule from being responsible for the long-unidentified diffuse interstellar bands. [ABSTRACT FROM AUTHOR] |
