Heterometallic Complexes Based on the Mixed Bridging Ligands of Tricyanometalate and Terephthalate: Syntheses, Structures, and Magnetic Properties

摘要

With the use of the tailored tricyanometalate precursors [(L)Fe(CN)(3)](-) (L = Tp, tris(pyrazolyl)hydroborate; L = i-BuTp, 2-methylpropyltris(pyrazolyl)borate) and terephthalate (ta) units as the mixed bridging ligands, a new one-dimensional (1D) chain polymer {[(Tp)(2)Fe-2(CN)(6)Cu-2(ta)(dmbpy)(2)]center dot 7H(2)O}(n) (1), a pentanuclear heterometallic cluster [(Tp)(2)Fe-2(CN)(6)Cu-3(phen)(3)(ta)(2)(MeOH)(H2O)(2)]center dot 8H(2)O (2), and a tetranuclear heterometallic cluster [(i-BuTp)(2)Fe-2(CN)(6)Cu-2(ta)(phen)(2)(EtOH)(2)]center dot 2MeOH center dot H2O (3) (dmbpy = 4,4'-dimethyl-2,2'-bipyridyl, phen = 1,10-phenanthroline) have been synthesized and structurally characterized. The Fe-III and Cu-II ions are bridged by cyanides, and the Cu-II ions are further linked by terephthalate to form the 1D chain polymer, the pentanuclear cluster, and the tetranuclear cluster for complexes 1-3, respectively. All complexes show ferromagnetic interactions between the Fe-III and Cu-II ions. Complex 1 shows metamagnetic behavior with the critical field of about 1.2 T at 1.8 K.