| Abstract
| - Positive and negative ions generated by laser-basedionization methods from three gold:thiolate cluster compounds are mass analyzed by time-of-flight mass spectrometry. The three compounds have similar inorganiccore masses (∼29 kDa, ∼145 Au atoms) but differentn-alkanethiolate ligands associated with each clustercompound (Au:SR, R = butane, hexane, dodecane).Irradiation of neat films (laser desorption/ionization) andfilms generated by dilution of the cluster compounds inan organic acid matrix (matrix-assisted laser desorption/ionization) with a nitrogen laser (337 nm) produceddistinct ion abundances that are relevant to differentstructural aspects of the cluster compound. Laser desorption/ionization of neat Au:SR compound films produces ions consistent with the inorganic core mass (i.e.,devoid of original hydrocarbon content). Matrix-assistedlaser desorption/ionization produces either ions with m/zvalues consistent with the core mass of the clustercompounds or ions with m/z values consistent with theapproximate molecular weight of the cluster compounds,depending on ionization conditions. The ion abundances,and ionization conditions under which they are detected,provide insight into desorption/ionization processes forthese unique cluster compounds as well as other analytestypically studied by matrix-assisted laser desorption/ionization.
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