Formation of the highly unusual cyclic clusters [MH(CO)4]n (M = Mn, n = 4–9; M = Re, n = 4–6) under laser desorption/ionisation conditions

Abstract

The positive and negative ion ultraviolet laser desorption mass spectra of the trinuclear clusters [M₃H₃(CO)₁₂] (M = Mn 1 or Re 2) have been recorded using laser desorption/ionisation time-of-flight mass spectrometry (LDI-TOF-MS). The spectra contain peaks corresponding to trinuclear clusters together with peaks at higher masses arising from the series of condensed products [M_nH_n − 1(CO)_4n]⁻ (where n = 4–9). These products are believed to have cyclic structures and to be formed by the stepwise insertion of [MH(CO)₄] into a metal–metal bond.