Photodissociation spectroscopy of (C₆H₆)₂^PLU

The photodissociation spectrum of (C₆H₆)₂^PLU is obtained from the yields of fragment C₆H₆^PLU ion as a function of photodissociation wavelength in the 400-1400 nm region. Two bands at 440 and 580 nm are attributed to the C ← X and the B ← X local excitation (LE) bands, respectively. Both the most intense band at 920 nm and relatively weak one at 1160 nm are assigned to charge resonance (CR) bands. The red-shift of the B ← B band from the of C₆H₆^PLU and the cross section at the CR bands much larger than those at the LE bands are consistent with a sandwich structure for (C₆H₆)₂^PLU. The appearance of the two CR bands is explained on the basis of displaced sandwich structures for (C₆H₆)₂^PLU.