Exchange parameters of five-spin clusters of Cu(II) coordination compounds with imidazoline nitroxide radicals

Abstract

The exchange Heisenberg interaction parameters have been determined from theoretical analysis of the temperature dependence of magnetic susceptibility of coordination cluster compounds [Cu(hfacac)2]3(Li(i))2 (hfacac is hexafluoroacetylacetonate, L(i) are 3-imidazoline nitroxides). Upon coordination of both N ∸ O oxygens and heterocycle N(3) atoms by Cu2+ ions, the interactions are ferromagnetic in nature and have the same order of magnitude. The minor intercluster interactions are antiferromagnetic.