We report the syntheses and characterizations, in the solid state and in solution, of three new cyclic polyoxothiomolybdates self-assembled around 2, 5-dimethylterephthalate (DMT) and 2, 5-bis (trifluoromethyl) terephthalate (DFMT) ligands, namely [Mo 12 DMT] 2−,[Mo 12 DFMT] 2− and [Mo 16 DFMT] 2−. A series of these two Mo 12-compounds completed by the two Mo 12-compounds obtained with 2, 3, 5, 6-tetramethylterephthalate and trimesate ...