Bis(mu-cystamine-kappa4N,S:S',N')bis[(2-aminoethanethiolato-kappa2N,S)-iridium(III)] tetrabromide dihydrate.

In the complex cation of the title compound, [Ir2(C2H6NS)2(C4H12N2S2)2]Br4.2H2O, which was obtained by rearrangement of [Re[Ir(aet)3]2]3+ (aet is 2-aminoethanethiolate) in an aqueous solution, two approximately octahedral fac(S)-[Ir(NH2CH2CH2S)3] units are linked by two coordinated disulfide bonds. The complex cation has a twofold axis, and the two non-bridging thiolate S atoms in the complex are located on opposite sides of the two disulfide bonds. Considering the absolute configurations of the two octahedral units (Delta and Lambda) and the four asymmetric disulfide S atoms (R and S), the complex consists of the Delta(RR)Delta(RR) and Lambda(SS)Lambda(SS) isomers, which combine to form the racemic compound.