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Updated: Aug 8, 2026
Magnetometric Characterization of Intermediates in the Solid-State Electrochemistry of Redox-Active Metal-Organic Frameworks
Published on: June 9, 2023
Construction of 3d-4f mixed-metal complexes based on a binuclear oxovanadium unit: synthesis, crystal structure, EPR,
Wei Shi1, Xiao-Yan Chen, Bin Zhao
1Department of Chemistry, Nankai University, Tianjin 300071, People's Republic of China.
Abstract:
The oxovanadium(IV)-lanthanide(III) heteronuclear complexes, [[Ce(H2O)7(VO)(TTHA)0.5][(VO)2(TTHA)]].8H2O (2), [Pr(H2O)7(VO)3(TTHA)1.5].10H2O (3), and [Nd(H2O)7(VO)3(TTHA)(1.5)].10H2O (4) (H6TTHA = triethylenetetraaminehexaacetic acid), were prepared based on a binuclear building block of [(VO)2(TTHA)]2- in [VO(H2O)5][(VO)2TTHA].4H2O (1). The X-ray crystallographic studies show that 1 is an ion-pair complex, containing the [(VO)2(TTHA)]2- unit as a useful building block. Adding the light Ln3+ ions to this synthesis system, three new 3d-4f mixed-metal-based complexes were obtained. Although the light lanthanide ions always exhibit similar chemical behavior, the structures of 2-4 are not homologous. 2 is exhibited as a one-dimensional coordination polymer, comprising an unusual Ce2V2 heterometallic lattice in the chain structure, which is the second report of a oxovanadium(IV)-lanthanide(III) coordination polymer. 3 and 4 are isomorphic, every two of the Ln3+ cations linked three [(VO)2(TTHA)]2- anions, forming an interesting linear octanuclear structure. This kind of heteronuclear linear complex is rather rare, which expands the realm of 3d-4f complexes. Further investigations such as IR spectra, UV-vis spectra, magnetic properties, and EPR spectra were studied, and a detailed discussion is given for this system.
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