A mixed-spin Fe(II) tetranuclear cluster: Preparation, structure and magnetic property

A tetranuclear ferrous cluster, [(phen)2Fe(II)(CN)2Fe(II)(bpqa)]2(PF4)4 · H2O · (CH3OH)2 (abbreviated as 1-(PF6)4) (bpqa = bis(2-pyridylmethyl)(2-quinolylmethyl)amine, phen = 1,10-phenanthroline), has been synthesized via self-assembly reaction. Single-crystal X-ray diffraction analysis shows that 1-(PF6)4 is a tetranuclear cyanide-bridged ferrous cluster, which is crystallized in centrosymmetric C2/c space group of monoclinic crystal system. The temperature (5–300 K) dependent magnetic susceptibility of 1-(PF6)4 corresponds to a mixed-spin state with two high spin and two low spin Fe(II) ions within the cluster.