GAS-PHASE METAL CYANIDE CHEMISTRY - FORMATION, REACTIONS, AND PROPOSED LINEAR STRUCTURES OF COPPER(I) AND SILVER(I) CYANIDE CLUSTERS

When solid MCN (M = Cu or Ag) is ablated with single pulses of a focus ed Nd-YAG laser (1064 nm, 470-1600 MW cm(-2)), the ions detected by Fo urier transform ion cyclotron resonance mass spectrometry (FTICRMS) ar e [M(n)(CN)(n+1)](-) (M = Cu, n = 1-5; M = Ag, n = 1-4), [M(n)(CN)(n-1 )](+) (M = Cu, a = 1-6; M = Ag, n = 1-4), and, for M = Ag, Ag-2(+), Ag -3(+) and [Ag-4(CN)](+). Several mixed-metal species [CumAgn-m(CN)(n+1 )](-) and [CumAgn-m(CN)(n-1)](+) are produced on ablation of a CuCN:Ag CN mixture. Both [M(n)(CN)(n+1)](-) and [M(n)(CN)(n-1)](+) lose units of MCN on collision-induced dissociation in Ar(g). Reactions of both [ M(n)(CN)(n+1)](-) and [M(n)(CN)(n-1)](+) with gaseous NH3, H2S and CO have been followed using FTICRMS. With the anions no addition was dete cted but dissociation occurred, again by loss of MCN. Dissociation occ urred with the cations also, but was frequently accompanied by additio n, with bis-adducts predominant. The ranges of addition products detec ted are: [M(n)(CN)(n-1)(NH3)(x)](+) (M = Cu, n = 2, x = 1-3, n = 3; x = 1-3, n = 4, n = 1-2; M = Ag, n = 2, x = 1-2, n = 3, x = 1-3, and n = 4, x = 1-3); [M(n)(CN)(n-1)(SH2)x](+) (M = Cu or Ag, n = 1-4, x = 1-2 ); [M(n)(CN)(n-1)(CO)(x)](+) (M = Cu, n = 3-5, x = 1-2; M = Ag, n = 4, x = 1-2). At long reaction times complexes containing HCN are formed in small amount when [Cu-n(CN)(n-1)](+) reacts with H2S. Geometry opti mizations using density functional theory (DMol) show that the most st able structures for both aa[M(n)(CN)(n+1)](-) and [M(n)(CN)(n-1)](+) a re linear alternations of M and CN, in spear topology.