A novel 3D self-catenated coordination polymer with multiform helical chains

A novel noncentrosymmetric coordination polymer, namely, [Cd2L(H2O)2]·solvent (1) (H4L = tetrakis[4-(carboxyphenyl)oxamethyl]methane acid), has been successfully solvothermally synthesized and characterized by signal-crystal X-ray diffraction, IR spectra, element analysis, powder X-ray diffraction and thermogravimetric analysis. The structure study shows that 1 exhibits a 3D framework based on 1D carboxylate-metal chains. Furthermore, 1 contains three types of helical chains along the c axis. From a topological perspective, 1 can be reduced to a new self-catenated binodal (4,6)-connected (66)(615) topology. In addition, the second-order nonlinear optical and fluorescent properties of 1 have also been investigated.