Ligand and metal salts were dissolved in MeOH-H2O (7:3) and heated, in the ratios indicated below. Eu(III) complexes were heated in microwave reactor at 90°C for 30 minutes, while Ni(II) and Zn(II) complexes were formed by reflux overnight. Solvent was removed in vacuo and solids dried in oven at 60 °C.