Synthesis and Magnetic Studies of Binuclear Iron(II) Complexes Bridged by Tetracarboxylato Groups

• Autorzy: Li Y. , Yan C. -W.
• Języki publikacji: EN

Abstrakty

EN

Four novel binuclear iron(II) complexes, namely [Fe2(PMTA)L4], where L denotes 4,4_-dimethyl-2,2_-bipyridine (Me2-bpy); 1,10-phenanthroline (phen); 5-chloro-1,10- phenanthroline (Cl-phen) or 5-bromo-1,10-phenanthroline (Br-phen), respectively, and PMTA stands for the tetraanion of pyromellitic acid, have been synthesized and characterized. Based on elemental analyses, magnetic moments at room-temperature and molar conductivity measurements, and spectroscopic (electronic and IR spectra) studies, extended PMTA-bridged structures consisting of two iron(II) ions, each in a distorted octahedral environment, are proposed for these complexes. The variable temperature magnetic susceptibilities (4_300 K) of the complexes [Fe2(PMTA)(Me2-bpy)4] (1) and [Fe2(PMTA)(phen)4] (2) were measured and the magnetic analysis was carried out by least-square method to the observed data with the susceptibility equation derived from the spin Hamiltonian operator, _ _ _ H 2JS S 1 2 _ _ _ , giving the exchange integrals J = _1.09 cm_1 for (1) and J = ___18 cm_1 for (2). The results indicate that there is a very weak antiferromagnetic spin-exchange interaction between the Fe(II) ions within each molecule.

Słowa kluczowe

EN

mi-tetracarboxylato-bridge; binuclear iron(II) complexes; synthesis; magnetism

• Wydawca: Polskie Towarzystwo Chemiczne
• Czasopismo: Polish Journal of Chemistry
• Rocznik: 2002
• Tom: Vol. 76 / nr 12
• Strony: 1681--1687
• Opis fizyczny: Bibliogr. 20 poz., rys.

Twórcy

autor

Li Y.

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

autor

Yan C. -W.

• Ocean University of Qingdao, 5 Yushan Road, Qingdao, Shandong 266003, P. R. China

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