Synthesis,Crystal Structure and Properties of a 3-Fold Interpenetrating 3D Cd(Ⅱ) Complex Derived from 4-(2-Methyl-1H-imidazol-1-yl)benzoic Acid

A new Cd~Ⅱ coordination complex,namely [Cd(iba)_2]_n(1),was prepared by the hydrothermal reaction of Cd(NO_3)_2·4H_2O with 4-imidazol-1-yl-benzoic acid(Hiba). Single-crystal X-ray diffraction analysis shows that compound 1 crystallizes in monoclinic system,space group Cc with a = 11.403(4),b = 30.480(9),c = 7.732(3) ?,β = 130.189(4)o,V = 2503.0(1) ?~3,Z = 4,C_(22)H_(18)CdN_4O_4,Mr = 514.80,Dc = 1.666 g/cm~3,F(000) = 1032 and μ(Mo Kα) = 1.101 mm-1. The final R and wR are 0.0573 and 0.1823 for 4421 observed reflections with I 2σ(I). Each iba-ligand coordinates in a bidentate fashion,connecting the Cd(Ⅱ) atoms to form a 2D wave-shape layer structure,which can be simplified as a four-connected topological net. Interestingly,the 2D layers are further extended into a 3-fold interpenetrating 3D architecture. Compound 1 displays an emissive maximum at 455 nm in the solid state at room temperature and a response of the second harmonic generation(SHG) activity is approximately 0.8 times that of KDP.