Gavrilenko K. Synthesis and physico-chemical properties of homo- and heteropolynuclear m3-oxocarboxylic complexes of Fe3+, Cr3+, Mn2+, Co2+ and Ni2+

10 new homo- and heterometallic trinuclear m3-oxocarboxylic complexes of chromium(III) and iron(III) with manganese(II), cobalt(II) and nickel(II) were prepared according to original methodic. Complexes were examined by the methods of mas-spectrometry, derivatography, IR-, electronic and Messbauer spectroscopy, by magnetochemical techniques. X-ray crystal structures of 3 new complexes were determined. In all complexes metal ions had pseudooctahedral ligand environment. In all complexes metals atoms located in the corners of equilateral or isoceles triangles with m3--O atom on center. Messbauer spectroscopy was showed that electron transfer absence in heteronuclear complexes [Fe2IIIMІІO(CF3COO)6(H2O)3] (were МІІ = Mn, Co or Ni). Ir- and electronic spectra were typical for trimmer carboxylates. Spin frustration was founded in all homometallic complexes. It was found that replacement of Fe3+ on Fe3O set on М2+ ion increased Fe-Fe antiferromagnetic coupling. Type of metal(II) ions were not affected on J-values Fe-M2+. It was established that heteronuclear trifluoroacetates [Fe2IIIMІІO(CF3COO)6(H2O)3] (were МІІ = Mn, Co or Ni) catalyzed toluene oxidation in acetonitril solution on mild conditions by air oxygen. It was indicated that nanosized oxides МFe2O4 obtained by thermolysis of heterometallic acetates [Fe2IIIMІІO(CH3COO)6(H2O)3] (were МІІ = Mn, Co or Ni). Superparamagnetic properties of magnetic particles МFe2O4 were found. It was showed that these oxides had unidomain structure.