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Updated: May 2, 2026

Combining Solid-state and Solution-based Techniques: Synthesis and Reactivity of ChalcogenidoplumbatesII or IV
Published on: December 29, 2016
Unexpected explanation for the enigmatic acid-catalysed reactivity of [Fe4S4X4](2-) clusters
Ahmed Alwaaly1, Ian Dance, Richard A Henderson
1School of Chemistry, Newcastle University, Newcastle upon Tyne NE1 7RU, UK. richard.henderson@ncl.ac.uk.
Abstract:
Density functional calculations show that Fe-S clusters undergo unexpected large structural changes when protonated at S. Protonation of prototypical cubanoid [Fe4S4X4](2-) to [Fe4S3(SH)X4](-) (X = Cl, SR, OR) results in formation of doubly-bridging SH, severance of one Fe-S bond, and creation of a three-coordinate Fe. These findings explain previously enigmatic results concerning the reactivity of these clusters, including the rates of protonation, pKa data, and the kinetics of acid-catalysed ligand substitution.
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