A Three-Dimensional Porous Metal−Organic Framework with a Body-Centered Cubic Topology Constructed from 48-Membered Tetraicosanuclear Metallamacrocycle Based on in Situ Ligand Synthesis

A three-dimensional metal−organic framework [Cd3(μ4-mtta)3(N3)3]·2.5H2O with [Cd24(N3)24] tetraicosanuclear metallamacrocycle as secondary building units (SBUs) and helical character is formed by self-assembly and in situ ligand synthesis. Each tetraicosanuclear metallamacrocycle SBU connects to eight neighboring tetraicosanuclear metallamacrocycle SBUs through 5-methyl tetrazolate (mtta) ligands, resulting in a body-centered cubic (bcu) topology. Thermal stability, variable-temperature powder X-ray diffraction, and luminescence spectrum of the compound were also studied.

本研究通过自组装与原位配体合成法，制备得到一种以[Cd24(N3)24]二十四核金属大环作为次级结构单元（secondary building units, SBUs）且具有螺旋特征的三维金属有机框架（metal−organic framework, MOF），其化学式为[Cd3(μ4-mtta)3(N3)3]·2.5H2O。每个二十四核金属大环次级结构单元均可通过5-甲基四唑酸盐（5-methyl tetrazolate, mtta）配体与8个相邻的同类型次级结构单元相连，最终形成体心立方（body-centered cubic, bcu）拓扑结构。此外，本研究还对该化合物的热稳定性、变温粉末X射线衍射及发光光谱开展了表征与分析。