Collision-induced dissociation and density functional study of the structures and energies of cyclic C2nN5- clusters

In this paper, we report mass spectrometry studies on C2nN5- cluster ions b y collision-induced dissociation (CID). The mass-selected cluster ions were dissociated by collision with a crossed nitrogen beam and the fragment ion s were mass analyzed in a secondary mass spectrometer. Characterization of the species as cyano-substituted, planar five-membered rings is supported b y density functional theory (DFT) calculations. Based on the analysis of th e experimental and computational results, cluster structures, energies, and stabilities are discussed. (C) 2000 American Institute of Physics. [S0021- 9606(00)01921-8].