摘要：

Laser (1064 nm) ablation of pressed mixtures of red phosphorus with powders of the metals cobalt or nickel generates positive ions [MP y ] + ( y = 2,4,6,8) and negative ions [M x P y ] - , monitored by Fourier transform ion cyclotron resonance (FTICR) mass spectrometry. At least 110 negative ions have been identified, more for Co than for Ni. The ions [M x P y ] - are distributed through the range 2 ≤ x ≤ 16, 4 ≤ y ≤ 17, with [Co x P 8 ] - ( x = 2, 3, 4, 5), [Co x P 10 ] - ( x = 5, 6, 7), [Ni x P 6 ] - ( x = 4, 5, 7, 8), and [Ni x P 8 ] - ( x = 2, 3, 4, 6, 7) as more abundant ions. The best negative ion spectra are obtained with 10:1 M/P mixtures, and high laser powers. The preponderance of even numbers of P atoms suggests that P 2 units are bound to the metals, and this is supported by the collisional dissociation of [MP y ] + ions (M = Co and Ni, y = 2, 4, 6) where loss of P 2 is the major pathway. For both [CoP 8 ] + and [NiP 8 ] + initial loss of P 4 is important. The reactions of [MP 2 ] + , [MP 4 ] + and [MP 8 ] + with σ-ligands ammonia and methanol, and π-ligands C 2 H 2 , C 2 H 4 and C 6 H 6 , involve addition and substitution processes.

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