Photodissociation of acrylonitrile cluster anions

Acrylonitrile (AN: CH2CHCN) cluster anions, (AN)n− (2⩽n⩽9), were irradiated with a laser at photon energies of 1.17 and 2.33 eV, and mass spectra of fragment anions were observed by a time-of-flight mass spectrometer. The trimer and the hexamer anions, (AN)3− and (AN)6−, were found to be produced dominantly by the photodissociation. The results revealed, in comparison with our previous results on the photoelectron spectra and collision-induced dissociation of AN cluster anions, that the parent anion (AN)n− (n⩾3) consists of a polymerized cyclic trimer anion (AN)3−, a polymerized cyclic neutral trimer unit (AN)3 and AN molecule(s).