Femtosecond time-resolved laser desorption/ionization mass spectrometry of perylene crystals using Raman-induced vibrational excitation

Femtosecond pump–probe mass spectrometry was carried out for perylene crystals. Perylene crystals were vibrationally excited by a Raman-induced process using two near-infrared pulses, and then the perylene molecules were ionized by time-delayed probe pulses. The number of perylene ions was markedly enhanced by excitation of intramolecular vibrations in perylene, but it was enhanced very slightly by excitation of intermolecular vibrations. It was also found that dimer cations were desorbed earlier than monomer cations, reflecting the crystal structure of perylene.