Related Experiment Video
Updated: Feb 5, 2026
Synthesis of Single-Crystalline Core-Shell Metal-Organic Frameworks
Published on: February 10, 2023
Water-Stable Metal-Organic Framework for Effective and Selective Cr2O72- Capture through Single-Crystal to
Li Ma1, Jin Yang1, Bing-Bing Lu1
1Key Lab for Polyoxometalate Science, Department of Chemistry , Northeast Normal University , Changchun 130024 , People's Republic of China.
Abstract:
Effective and selective capture of environmentally toxic Cr2O72- from water is desirable for both environment protection and human health, but it still remains a significant challenge. We present a water-stable cationic metal-organic framework (MOF) with large nanotubular channels ( ca. 1.4 × 1.4 nm2), (1-Cl). Remarkably, the resulting porous material exhibits rapid aqueous-phase removal of Cr2O72- via an anion-exchange manner. Meaningfully, the capture and separation of aqueous Cr2O72- are highly selective even in the presence of other disturbing anions. More importantly, the crystal structure of 1-Cl after anion exchange (1-Cr2O7) could be determined by single crystal X-ray diffraction, elaborating the single-crystal-to-single-crystal (SC-SC) transformation. The Cr2O72- removal process by 1-Cl thus was directly uncovered by the crystal structure of Cr2O72--incorporated 1-Cr2O7.
Related Concept Videos
02:42Ionic Crystal Structures
Most monatomic ions behave as charged spheres, and their attraction for ions of opposite charge is the same in every direction. Consequently, stable structures for ionic compounds result (1) when ions of one charge are surrounded by as many ions as possible of the opposite...
02:58Crystal 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...
02:46Crystal Field Theory - Tetrahedral and Square Planar Complexes
Crystal field theory (CFT) is applicable to molecules in geometries other than octahedral. In octahedral complexes, the lobes of the dx2−y2 and dz2 orbitals point directly at the ligands. For tetrahedral complexes, the d orbitals remain in place, but with only four ligands located between the axes. None of the orbitals points directly at the tetrahedral ligands. However, the dx2−y2 and dz2 orbitals (along the Cartesian axes) overlap with the ligands less than the dxy,...
01:25Crystal Growth: Principles of Crystallization
Initiating crystallization involves manipulating the concentration of the solute and the temperature of the solution. Since crystal growth occurs when the ratio of concentration and solubility of the solute in the solvent...
02:32Bonding in Metals
02:51Metal-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...