Hydrothermal synthesis and characterization of a new three-dimensional hybrid zinc phosphate [Zn2(HPO4)2(4,4′-bipy)]·3H2O with neutral porous framework

Employing 4,4′-bipyridine as a bridged ligand, a new three-dimensional (3-D) hybrid zinc phosphate [Zn₂(HPO₄)₂(4,4′-bipy)]·3H₂O has been prepared under hydrothermal conditions and characterized by single crystal X-ray diffraction. This compound crystallizes in the monoclinic space group C2/c, with cell parameters, , , , β=90.21(3)°, and Z=4. The connectivity of the ZnO₃N and HPO₄ tetrahedra results in a 2-D neutral layer that with interesting 4,8² net along the bc plane. Furthermore, the 4,4′-bipyridine molecule links the 4,8² net into a 3-D structure. The water molecules sit in the middle of the channels and interact with the framework via hydrogen bonds. The compound exhibits intense photoluminescence at room temperature.