The complexes [PdCl 2 (pap)] (1) and [PtCl 2 (pap)] (2; pap = 2-phenylazopyridine) were synthesized by treating PdCl 2 or K 2 PtCl 4 , respectively, with pap and characterized by 1 H NMR spectroscopy and elemental analysis. Both these complexes, together with the previously reported complex [(az)Pd(µ-Cl) 2 -Pd(az)] (3; az = azobenzene), were also characterized by Xray crystallography. The structures of 1, 2, and 3 show a slightly elongated N-N azo double bond due to back-donation from the metal centers and a twisting of the uncoordinated part of the ligands with respect to the rest of the molecule. Cyclic voltammetry of 1, 2, 3, and the related complex