Reaction of Fe2S2+ with C2H2 studied with a radiofrequency ion trap/time-of-flight mass spectrometer

The reactivity of iron sulfide cluster ions with acetylene has been studied in a radiofrequency ion trap with a time-of-flight mass spectrometer. A newly built set-up is described in detail. The cluster ions are produced by laser ablation and stored in the ion trap for about one second to react with acetylene. The product ions as well as the remaining parent cluster ions are analyzed with the time-of-flight mass spectrometer. The Fe2S2+ cluster ion reacts efficiently with C2H2 and forms Fe2S2(C2H2)n+ (n⪕4). The structure of Fe2S2+ is discussed on the basis of the favorable attachment of two or four C2H2 molecules.