A Family of Cyanide-Bridged Molecular Squares: Structural and Magnetic Properties of [{M<sup>II</sup>Cl<sub>2</sub>}<sub>2</sub>{Co<sup>II</sup>(triphos)(CN)<sub>2</sub>}<sub>2</sub>]·<i>x</i>CH<sub>2</sub>Cl<sub>2</sub>, M = Mn, Fe, Co, Ni, Zn
收藏资源简介：
The syntheses, structures, and magnetic properties of a series of tetranuclear cyanide-bridged compounds are reported. This family of molecular squares, [{MIICl2}2{CoII(triphos)(CN)2}2] (M = Mn ([CoMn]), Fe ([CoFe]), Co ([CoCo]), Ni ([CoNi]), and Zn ([CoZn]), triphos = 1,1,1-tris(diphenylphosphinomethyl)ethane), has been synthesized by the reaction of CoII(triphos)(CN)2 and MCl2 (M = Mn, Co, Ni, Zn) or Fe4Cl8(THF)6 in a CH2Cl2/EtOH mixture. These complexes are isostructural and consist of two pentacoordinate Co(II) and two tetrahedral M(II) centers. The resulting molecular squares are characterized by antiferromagnetic coupling between metal centers that generally follows the spin-coupling model Stotal = SM(II)1 − SCo1 + SM(II)2 − SCo2. Magnetic parameters for all the complexes were measured using SQUID magnetometry. Additionally, [CoZn] and [CoMn] were studied by both conventional and high-frequency and high-field electron paramagnetic resonance.
