The redox equilibrium between dinuclear Cu-II mu-thiolate and Cu-I disulfide structures has been analyzed experimentally and via DFT calculations. Two new ligands, (LSSL2)-S-2 and (LSSL4)-S-4, and their Cu-II mu-thiolate and Cu-I disulfide complexes were synthesized. For (LSSL2)-S-2, these two redoxisomeric copper species are shown to be in equilibrium, which depends on both temperature and solvent. For (LSSL4)-S-4 the mu-thiolate species forms as the kinetic product and further evolves into the disulfide complex under thermodynamic control, which creates the unprecedented possibility to both species under the same reaction conditions. The energies of the mu-thiolate and disulfide complexes for two series of related ligands have been calculated with DFT; the results rationalize the experimentally observed structures, and emphasize the important role that steric requirements play in the formation of the Cull thiolate structure.