Ionic Crystals of Na{[TM(phen)3][Eu(dpa)3]}·17H2O (TM = Ni, Co): Single-Crystal Structure and Luminescence Properties

Two new 3D 3d–4f heterometallic ionic crystals Na{[Ni(phen)3][Eu(dpa)3]}·17H2O and Na{[Co(phen)3][Eu(dpa)3]}·17H2O were successfully prepared at room temperature by TM-1,10-phenanthroline and Eu-2,5-pyridinedicarboxylic acid as precursors. Structures of the compounds were described as the anions of [Ni(phen)3]2+ connect with each other by π···π interactions to form a 2D network, then, the anions of [Ni(phen)3]2+ and [Eu(dpa)3]3+ connect with each other by the hydrogen bonding (O···H–O–H···O) from water molecules, forming 3D network. Luminescence properties of the synthesized crystals were investigated.