Four structurally novel transition-metal-bridging risedronate-based polyoxomolybdates (PODs) were well established and characterized. The face-sharing {MoO6} octahedra are employed and compound 4 is the first example containing isomeric polyanions 4a and 4b in organophosphonate-based PODs. Magnetic investigations indicate that compounds 1 and 4 displays ferromagnetic and antiferromagnetic interactions, respectively.