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A dichlorophenyl substituted nitronyl nitroxide radical 2-(2,6-dichlorophenyl)-4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazole-3-oxide-1-oxyl (L) is prepared, its structure and magnetic properties are studied. It is shown that the interaction of bis(hexafluoroacetylacetonato)copper(II) [Cu(hfac)2] with L leads to the formation of the {[Cu(hfac)2][Cu(hfac)2L2]} heterospin complex whose crystal structure consists of pseudo-polymer chains formed by alternating single-spin [Cu(hfac)2] and three-spin [Cu(hfac)2L2] fragments. It is established that the temperature dependence of magnetic susceptibility of {[Cu(hfac)2][Cu(hfac)2L2]} is determined by ferromagnetic exchange interactions between unpaired electrons of Cu(II) ions and the axially coordinated L in three-spin fragments. [ABSTRACT FROM AUTHOR]

Hydrolysis of the 4-nuclear [Cu(hfac)(MeO)]4 complex (where hfac is the hexafluoroacetylacetone ion) can be used as a convenient way to obtain the 11-nuclear complex [Cu11(hfac)10(OH)8(O)2] · 2MePh. The structure of the latter is determined using X-ray diffraction. [ABSTRACT FROM AUTHOR]

The structure of heterospin complexes[M(DCA)2L2x]·yH2O, where M = Mn, Co, Ni, Cu, Lx is the nitronyl nitroxide radical; DCA is the dicyanamide anion, y = 0, 1, or 2 is studied. It is found that the nature of[M(DCA)2L2x]·yH2O is characterized by the formation of multiple hydrogen bonds generating ribbons, layers, or frameworks in the crystals. The analysis of magnetostructural correlations by means of band calculations of the electronic structure confirms the occurrence of ferromagnetic exchange between the unpaired electrons of paramagnetic centers in solid [Cu(DCA)2L21]·2H2O when the distances between the copper ion and the coordinated N-O group are short. [ABSTRACT FROM AUTHOR]