Two d10-metal-organic frameworks based on polydentate Schiff-base ligand derived from biphenyl dihydrazide: Synthesis, crystal structure and luminescent properties

Abstract: Two two-dimensional d10-metal-organic frameworks {[CdL2(NO3)2]·(H2O)6} n (1) and {[Zn2L4(NCS)4]·(H2O)4·(CH3OH)} n (2) have been synthesized and characterized by IR, elemental analyses, XRPD, TG technique and complete X-ray single crystal structure analyses, where L is bis(pyridin-3-ylmethylene)biphenyl-2,2′-dicarbohydrazide. The two polymers display similar 2D layer network containing tetranuclear metallacyclic ring units [MII 4L4] (M=Cd (1) and Zn (2)) in the chair conformation, in which each ligand L acts as a bidentate bridging ligand to bind two metal centers through two terminal pyridyl N-donors. The solvent molecules were filled into the macrometallacyclic ring units through multiform hydrogen bonds. In addition, the Cπ interactions are found in the 2D networks and also play an important role in stabilizing the networks. The luminescent properties of 1 and 2 were investigated in the solid state at room temperature. [Copyright &y& Elsevier]