Protonation on the core sites of [Fe4X4(Y-n-C12H25)4]2–(X, Y = S and Se) in aqueous micellar solutions

Abstract

The pK_a values of [Fe₄S₄(Y-n-C₁₂H₂₅)₄]^2– and [Fe₄Se₄(Y-n-C₁₂H₂₅)₄]^2–(Y = S and Se) in non-ionic micellar solutions have been determined as 8.9–9.1 and 7.7, respectively, suggesting that the protonation of the clusters takes place on the sulphur or selenium atoms of the Fe₄X₄ core (X = S and Se) rather than on the terminal alkyl-thiolate and -selenolate ligands.