Salt of dysprosium(iii) tetrakis(hexafluoroacetylacetonate) with 1,1′-dimethyl-4,4′-bipyridinium as a new single-ion magnet
摘要
Two complex dysprosium(iii) salts of composition Na[Dy(hfac)4] (1) and Q[Dy(hfac)4]2 (2), where hfac is the hexafluoroacetylacetonate anion and Q is 1,1′-dimethyl-4,4′-bipyridinium, were synthesized and studied by X-ray diffraction. An analysis of the X-ray diffraction data using the Shape program revealed noticeable distortions of two [DyO8] coordination polyhedra of salt 2 anions; the Dy atoms are nonequivalent and have a biaugmented trigonal prismatic (C2v) and triangular dodecahedral (D2d) geometry. The experimental studies and the analysis of the magnetic properties of 2 showed that this compound exhibits a field-induced slow relaxation of magnetization, which is described by the Orbach mechanism (Ueff = 23.0 K, τ0 = 2.68 · 10−8 s).