LASER IONIZATION MASS-SPECTROMETRY OF HOMOGENEOUS AND BINARY MOLECULAR CLUSTERS OF NITRIC-OXIDE

A potpourri of binary heteroclusters of the form (NO)(m)(Y)(n) has bee n investigated by coexpansion of the two components (along with argon) in a supersonic nozzle. They are subsequently ionized by picosecond, nonresonant, two-photon absorption and characterized by mass spectrome try. Neat (NO)(m)(+) clusters exhibit an odd-even intensity alternatio n which is attributed to electron pairing effects. A varied set of par tners for the binary nitric oxide clusters includes N2O, NO2, H2O, CO2 , CS2, SO2, and SF6. The observed cluster distributions are discussed in terms of cluster formation and decay mechanisms and relative bond s trengths. Possible structures for some especially stable species act d iscussed. Of special interest are the observations of especially stabl e (NO)(3)(+)(Y)(n) compounds where Y represents the isovalent N2O, CO2 , or CS2 partners. SF6 and its clusters also form notably stable clust ers with the nitric oxide trimer ion.