Infrared photodissociation spectroscopy of benzene-Ne,Ar complex cations

The infrared (IR) absorption spectrum of the jet-cooled benzene cation complexed with Ne has been recorded throughout the 275-1600 cm(-1) and the 2800-3200 cm(-1) ranges via IR-laser induced vibrational dissociation spectroscopy. Measuring the spectrum of the complex ion rather than the spectrum of the bare benzene cation, leads to the appearance of weak Van der Waals sidebands. In addition, subtle effects of the symmetry lowering in the complex, giving rise to additional lines in the spectrum, have been observed for the benzene-Ar complex. To obtain a more detailed picture of the vibrational structure of the benzene cation in the region up to 1500 cm(-1), IR absorption spectra of benzene complex cations prepared in selected low-lying vibrationally excited levels have been recorded.