Three novel coordination polymers, [Ni2(tib)2(btec)]·2H2O (1), [Co2(tib)2(btec)]·2H2O (2) and [Zn4(tib)2(btec)Cl4]·2H2O (3), have been synthesized by using mixed ligands of 1,3,5-tris(1-imidazolyl)benzene (tib) and 1,2,4,5-benzenetetracarboxylic acid (H4btec) under hydrothermal conditions. Complexes 1 and 2 have the same structure and are rare three-dimensional (3D) self-penetrating (3,4,5)-connected nets, while complex 3 is an unprecedented (3,4)-connected 3D net. The different structures of 1 (2) and 3 are ascribed to the distinct coordination geometry of the metal centers. The thermal stability and photoluminescence property of the complexes were investigated.
SU Zhi, FAN Jian & SUN WeiYin State Key Laboratory of Coordination Chemistry
A novel compound, （IBzQI）（TCNQ）2 2 （IBzQ1=1-（4-iodobenzyl）quinolinium and TCNQ = 7,7,8,8-tetracyanoquinodimethane） has been fabricated and X-ray single-crystal structurally analyzed. This compound crystallizes in the triclinic system, space group P1 with a = 8.3540（17）, b = 13.284（3）, c = 16.185（3） А, α= 82.12（3）, β= 75.19（3）, γ= 72.34°, V = 1651.2（6） А^3, Z= 2, C_40H_21IN_9, Mr = 754.56, Dc = 1.518 g/cm^3,μ= 1.015 mm^-1, S = 1.010, F（000） = 754, R = 0.0387 and wR = 0.0948. The structure analysis shows that the anions are stacked into column with tetrads, and there are two types of TCNQ entries （TCNQ-1 and TCNQ^0） in agreement with the IR spectra analysis of the compound. The temperature dependence of the magnetic susceptibility （2-300 K） for 2 exhibits spin gap of singlet-triplet feature, and the best fit gave △/kB = 1523.4 K. In order to understand both magnetic behavior and local charge distribution of [（TCNQ）2]-unit, the molecular orbital calculations and analysis based on extended Hückel method were performed, and the results support the analyses of both crystal structure and IR spectra.
