Synthesis and Magnetic Properties of Dinuclear Oxovanadium(IV) Complexes Bridged by Tetracarboxylato Groups

• Autorzy: Li, Y. , Yan, C. , Guan, H.
• Języki publikacji: EN

Abstrakty

EN

Three novel _-tetracarboxylato-bridged oxovanadium(IV) dinuclear complexes described by the overall formula [(VO)2(PMTA)L2], where PMTAstands for the tetraanion of pyromellitic acid, and L denotes 2,2_-bipyridine (bpy), 4,4_-dimethyl-2,2_-bipyridine (Me2bpy) or 1,10-phenanthroline (phen), respectively, have been synthesized and characterized by elemental analyses, molar conductivity and room-temperature magnetic moment measurements, IR, ESR and electronic spectral studies. It is proposed that these complexes have PMTA-bridged structures and consist of two oxovanadium(IV) ions, each in a square-pyramidal environment. The [(VO)2(PMTA)(bpy)2] (1) and [(VO)2(PMTA)(phen)2] (2) complexes were further characterized by variable temperature (4.2~300 K) magnetic susceptibility measurements and the observed data were fitted to the modified Bleaney-Bowers equation by the least-squares method, giving the exchange integral J = -2.75 cm-1 for (1) and J = -3.91 cm-1 for (2). This result indicates that there is a weak antiferromagnetic spin-exchange interaction between the two VO2+ ions within each molecule.

Słowa kluczowe

EN

mi-tetracarboxylato-bridge; oxovanadium(IV); dinuclear complexes; magnetic properties

• Czasopismo: Polish Journal of Chemistry
• Rocznik: 2004
• Tom: Vol. 78 / nr 1
• Strony: 1-7
• Opis fizyczny: Bibliogr. 28 poz., rys.

Twórcy

autor

Li, Y.

• Marine Drug & Food Institute, Ocean University of China, 5 Yushan Road, Qingdao, Shandong 266003, P. R. China

autor

Yan, C.

• College of Marine Life Sciences, Ocean University of China, Qingdao, 266003, P. R. China

autor

Guan, H.

• Marine Drug & Food Institute, Ocean University of China, 5 Yushan Road, Qingdao, Shandong 266003, P. R. China

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