DFT study of the intrinsic conformations of [2Fe-2S-4(SCH3)]2− clusters and their influence on exchange coupling

The equilibrium conformations of diiron(III) cluster [2Fe-2S-4(SCH3)]2− have been determined using density functional theory. The relative conformer energies depend on a small number of side-chain repulsion parameters. Ten of the 17 possible conformations are stable in both the ferromagnetic and broken symmetry state. The cartoon shows the conformation with the lowest energy. Conformation has a moderate influence on J.