Two new mononuclear coordination complexes constructed by non-covalent interactions, [Ni(phen)2(H2O)2](ClO4)2 (1) and [Cd(ClO4)2(phen)2] (2), where phen=1,10-phenanthroline, were synthesized and characterized by single-crystal X-ray diffractometry. The structural determination revealed that the coordination geometry around the Ni/Cd centres is distorted octahedral for each complex. In the complexes 1 and 2 the metal atoms have N4O2 coordination cores. In 1 the intermolecular OH···O hydrogen bonds, which involve the coordinating water molecules as donors and the perchlorate O atoms as acceptors form zigzag-like hydrogen-bonding chains, which are further assembled via π-π stacking interactions between adjacent phen rings, thus forming a supramolecular network structure. In the crystal structure of 2, π–π stacking interactions are noted between neighbouring hydrophobic phen ligands, yielding 1D supramolecular chains. The luminescence studies show that compound 1 displays blue luminescence, while compound 2 – white-light emission upon excitation with ultraviolet light.