Investigating the Thermolysis Products of [Cd10Se4(SePh)12(P n Pr3)4] – The New Cluster Ion [Cd17Se4(SePh)28]2?

Analytical studies on the thermolysis products from [Cd₁₀Se₄(SePh)₁₂(PnPr₃)₄] are reported leading to the identification of the doubly negatively charged species [Cd₁₇Se₄(SePh)₂₈]²⁻. Electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI FT-ICR MS) has been successfully applied to analyse the composition of a polycrystalline precipitate after treatment with SePh⁻ in tetrahydrofuran (THF). Presumably, SePh⁻ reacts with the insoluble (polymeric) cluster product as a charging ligand leading to dissolved monomeric units of the cluster anion [Cd₁₇Se₄(SePh)₂₈]²⁻. This cluster anion could also be crystallized from solutions as [Na(thf)₂18-crown-6][Cd₁₇Se₄(SePh)₂₈] and [Na(dme)₃]₂[Cd₁₇Se₄(SePh)₂₈]. The experimental results promise a wider applicability of the charged ligand exchange method for the electrospray mass spectrometric characterization of neutral clusters and to obtain intensive monodisperse cluster ion beams for further gas-phase studies. Dedicated to Prof. Dieter Fenske on the occasion of his 65th birthday.