MOE Laboratory of Bioinorganic and Synthetic Chemistry, School of Chemistry & Chemical Engineering, Sun Yat-Sen University, Guangzhou 510275, China.
Chemistry. 2010 Feb 8;16(6):1841-8. doi: 10.1002/chem.200901929.
Two series of microporous lanthanide coordination networks of the general formula, {[Ln(ntb)Cl(3)] x xH(2)O}(n) (series 1: monoclinic C2/c, Ln = Sm and Tb; series 2: hexagonal P3(1)/c, Ln = Sm and Eu; ntb = tris(benzimidazol-2-ylmethyl)amine, x = 0-4) have been synthesized and characterized by IR, elemental analyses, thermal gravimetry, and single-crystal and powder X-ray diffraction methods. In both series, the monomeric [Ln(ntb)Cl(3)] coordination units are consolidated by N-H...Cl or C-H...Cl hydrogen bonds to sustain three-dimensional (3D) networks. However, the different modes of hydrogen bonding in the two series lead to crystallization of the same [Ln(ntb)Cl(3)] monomers in different forms (monoclinic vs. hexagonal), consequently giving rise to distinct porous structures. The resulting hydrogen-bonded coordination networks display high thermal stability and robustness in water removal/inclusion processes, which was confirmed by temperature-dependent single-crystal-to-single-crystal transformation measurements. Adsorption studies with H(2), CO(2), and MeOH have been carried out, and reveal distinct differences in adsorption behavior between the two forms. In the case of MeOH uptake, the monoclinic network shows a normal type I isotherm, whereas the hexagonal network displays dynamic porous properties.
已合成并通过红外光谱、元素分析、热重分析、单晶和粉末 X 射线衍射方法对通式为{[Ln(ntb)Cl(3)] x xH(2)O}(n) 的两个系列微孔镧系配位网络进行了表征（系列 1：单斜 C2/c，Ln = Sm 和 Tb；系列 2：六方 P3(1)/c，Ln = Sm 和 Eu；ntb = 三（苯并咪唑-2-基甲基）胺，x = 0-4）。在两个系列中，单体[Ln(ntb)Cl(3)]配位单元通过 N-H…Cl 或 C-H…Cl 氢键连接在一起，以维持三维（3D）网络。然而，两种系列中不同的氢键模式导致相同的[Ln(ntb)Cl(3)]单体以不同的形式（单斜晶系与六方晶系）结晶，从而产生不同的多孔结构。由此产生的氢键配位网络在水去除/包含过程中表现出高的热稳定性和稳健性，这通过温度依赖性单晶到单晶转变测量得到了证实。已经进行了对 H(2)、CO(2)和 MeOH 的吸附研究，结果表明两种形式的吸附行为存在明显差异。在 MeOH 吸收的情况下，单斜网络显示出正常的 I 型等温线，而六方网络则显示出动态多孔特性。
