A Novel Zinc(II) Supramolecular Complex with Open 2D Channels

Abstract

) crystallizes in orthorhombic I222 space group and exhibits a unique 3D supramolecular network containing open 2D channels along the a- and b-axis. In the asymmetric unit, there is only one crystallographically independent Zn(II) ion, one PZDC ligand, half of coordinated 4,4'-bpy as well as half of free 4,4'-bpy molecule, and two coordinated water molecules together with one free water molecule. The Zn(II) ion is six-coordinated, by two nitrogen atoms and one oxygen atom from one PZDC ligand, one nitrogen atom from one 4,4'-bpy molecule and two oxygen atoms from two water molecules. Therefore, the local coordination geometry of Zn(II) ion is in a distorted octahedron with a N2O4 donor net and is shown in Figure 1. In the title complex, the coordinated 4,4'-bpy molecule bridges two Zn(II) ions to generate a binuclear unit. Such bi-nuclear units as the building blocks are linked by rich hydro-gen bonds and π-π stacking interactions into 3D supra-molecular network, which has open 2D channels and the channels volume is 37.8% of the total crystal volume as esti-mated by PLATON. Interestingly, in the complex the shape and size of the two channels are different. Along the a-axis, these 1D supramolecular chains are arranged alternatively by hydrogen bonds between the coordinated water molecule and the uncoordinated carboxylate oxygen atoms into 3D supra-molecular network containing the 1D rectangular channels with the dimension of approximate 10.131×10.652 A