Related Experiment Video
Updated: Aug 6, 2026

Experimental Approaches for the Synthesis of Low-Valent Metal-Organic Frameworks from Multitopic Phosphine Linkers
Published on: May 12, 2023
Construction of Multiply Bridged Coordination Framework via a Cluster-Ligand Strategy
Jia-Hong Huang1, Feng Xiao2, Zhihe Liu1
1Department of Chemical and Biomolecular Engineering, National University of Singapore, Singapore, Singapore.
None:
In the context of reticular chemistry, linking secondary building units (SBUs) through multiple bridging modes could enhance structural robustness and facilitate the development of versatile frameworks. However, the deliberate synthesis of coordination frameworks by these multiply bridged SBUs remains challenging, as the component SBUs are typically generated in situ during framework assembly. Here, we report facile synthesis of a multiply bridged coordination framework via a cluster-ligand strategy, where pre-functionalized metal nanoclusters (NCs) with high-density coordination sites are used as multi-bridging linkers to transition metal cluster nodes. Specifically, a predesigned [Au25(p-MBA)18]-1 (p-MBA = p-mercaptobenzoic acid) NC, featuring peripherally decorated 18 carboxyl groups in a self-adjustable and environmentally adaptive configuration, functions as both SBUs and highly coordinated linkers. This highly coordinated [Au25(p-MBA)18]-1 assembles into a (4,8)-connected rhombic dodecahedral framework (Au25-Zn5) through doubly and triply bridging to Zn5 clusters. The ordered co-assembly enhances the near-infrared (NIR) emission of [Au25(p-MBA)18]-1 and yields supercrystals suitable for x-ray crystallography analysis, providing a good means to resolve the structural and luminescence enhancement mechanism of water-soluble metal NCs. Leveraging the enhanced NIR emission and improved structural stability assured by the multiple bridging modes, Au25-Zn5 could serve as a versatile and leak-free NIR-emissive coating for real-time image-guided tumor surgery.
Related Concept Videos
Metal-Ligand Bonds
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...
Structural Isomerism
Isomers are different chemical species that have the same chemical formula. Structural isomerism of coordination compounds can be divided into two subcategories, the linkage isomers and coordination-sphere isomers.
Linkage isomers occur when the coordination compound contains a ligand that can bind to the transition metal center through two different atoms. For example, the CN− ligand can bind through the carbon atom or through the nitrogen atom. Similarly, SCN− can be...
Crystal Field Theory - Octahedral Complexes
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
Ligand Binding and Linkage
Ligand Binding and Linkage
Coordination Number and Geometry

