Liu Chao, Chen Fang-Yuan, Tian Hong-Rui, Ai Jing, Yang Weiting, Pan Qing-Jiang, Sun Zhong-Ming
State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences , 5625 Renmin Street, Changchun, Jilin 130022, China.
University of Chinese Academy of Sciences , Beijing 100049, P. R. China.
Inorg Chem. 2017 Nov 20;56(22):14147-14156. doi: 10.1021/acs.inorgchem.7b02274. Epub 2017 Nov 1.
Two novel three-dimensional interpenetrated uranyl-organic frameworks, (NH)[(UO)(L)]·6HO (1) and [(UO)(HO)L]·2HO (2), where L = tetrakis(3-carboxyphenyl)silicon and L = tetrakis(4-carboxyphenyl)silicon, were synthesized by a combination of two isomeric tetrahedral silicon-centered ligands with 3-connected triangular [(UO)(COO)] and 4-connected dinuclear [(UO)(COO)] units, respectively. Structural analyses indicate that 1 possesses a 2-fold interpenetrating anion bor network, while 2 exhibits a 3-fold interpenetrated 4,4-connected neutral network with pts topology. Both compounds were characterized by thermogravimetric analysis and IR, UV-vis, and photoluminescence spectroscopy. A relativistic density functional theory (DFT) investigation on 10 model compounds of 1 and 2 shows good agreement of the structural parameters, stretching vibrational frequencies, and absorption with experimental results; the time-dependent DFT calculations unravel that low-energy absorption bands originate from ligand-to-uranium charge transfer.
合成了两种新型的三维互穿铀酰有机框架化合物，(NH)[(UO)(L)]·6HO (1) 和 [(UO)(HO)L]·2HO (2)，其中L = 四(3-羧基苯基)硅和L = 四(4-羧基苯基)硅，分别通过两种异构的以硅为中心的四面体配体与3-连接的三角形[(UO)(COO)]和4-连接的双核[(UO)(COO)]单元组合而成。结构分析表明，1具有一个2重互穿的阴离子硼网络，而2呈现出一个具有pts拓扑结构的3重互穿的4,4-连接的中性网络。通过热重分析以及红外、紫外可见和光致发光光谱对这两种化合物进行了表征。对1和2的10种模型化合物进行的相对论密度泛函理论(DFT)研究表明，其结构参数、伸缩振动频率和吸收与实验结果吻合良好；含时DFT计算表明，低能吸收带源于配体到铀的电荷转移。
