Seven polyoxometalate-based compounds were synthesized under hydrothermal conditions, namely [Co(H2Ptep)(HPtep)(H2O)2(PW11CoO39)]·4.5H2O (1), {[Cu(H3Ptep)2(H2Ptep)2][SiW12O40]}·(SiW12O40)2·8H2O (2), {Cu3(H2Ptpi)2(Ptpi)2(H2O)5[(PMo11CuO39)2]}·6H2O (3), [Co(H2Ptpi)2(HPtpi)2(SiMo12O40)2]·2H2O (4), [Co3(Ptpi)2(H2O)6(TeMo6O24)]·2H2O (5),[Co2Na(HPtpi)(H2O)7.5(TeMo6O24)]·3.5H2O (6), [Cu(HZtpi)(H2O)2(CrMo6(OH)6O18)]·5H2O (7) (Ptep = 1-[2-(3-Pyridin-4-yl-[1,2,4]triazol-4-yl)-ethyl]-piperazine, Ptpi = 1-[2-(3-Pyridin-4-yl-[1,2,4]triazol-4-yl)-propyl]-imidazol, Ztpi =...