Structure, spectra, and intracluster chemistry of gas-phase platinum nitrosyl ion–molecule complexes

Abstract

The structures of gas-phase platinum nitrosyl ion–molecule complexes, [Pt(NO)_n]⁺ (n = 3–7), have been investigated using a combination of infrared photodissociation action spectroscopy and quantum chemical simulations. Nitric oxide binds in a combination of linear and bent motifs associated with nominal three- and one-electron donation, respectively, and there is clear evidence of a first solvation shell closing at six ligands. Oxygen rich complexes are also observed in the mass spectrum and their infrared spectra indicate the formation of an N₂O₃ moiety. Calculations support the interpretation of [Pt(N₂O₃)(NO)_n]⁺ complexes arising from exothermic intracluster reactions in which [⋯(NO)₃⋯]⁺ complexes form [⋯(NO₂)(N₂O)⋯]⁺ species from which the more weakly-bound nitrous oxide is lost.