Two W/Cu/S clusters: tetraethylammonium bromidodi-μ2-sulfido-sulfido[tris(3,5-dimethylpyrazol-1-yl)borato]copper(I)tungsten(VI) and tetraethylammonium dibromido-μ3-sulfido-di-μ2-sulfido-[tris(3,5-dimethylpyrazol-1-yl)borato]dicopper(I)tungsten(VI).