High-Spin Metal Complexes Containing a Ferromagnetically Coupled Tris(semiquinone) Ligand
作者:Andrea Caneschi、Andrea Dei、Christopher P. Mussari、David A. Shultz、Lorenzo Sorace、Kira E. Vostrikova
DOI:10.1021/ic0106322
日期:2002.3.1
giving rise to complexes with S = 9/2 (M = Ni(II)) and S = 6 (M = Mn(II)) ground states. The coupling within the tris(semiquinone) unit is quite large (J = -26 cm(-1) for the nickel(II) derivative and J = -40 cm(-1) for the manganese(II) one, using the general exchange Hamiltonian H = sigma J(ij)S(i)S(j)), and it is of the same order of magnitude as that observed in an analogous series of bis(semiquinone)
合成了三齿双配体1,3,5-三(5'-叔丁基-3',4'-二羟基苯基)苯((TBCat)(3)Ph)。该分子在碱性溶液中与两个顺磁性受体,即镍(II)负号四氮杂大环配体配合物(Ni(CTH))(CTH = dl-5,7,7,12,14,14-hexamethyl-1)的反应,4,8,11-四氮杂十四烷)和锰(II)-氢三[3-(4'-枯烯基)-5-甲基吡唑基]硼酸酯(Mn(Tp(Cum,Me))),得到两种配合物,其分析式为与三核复合物一致。光谱和磁测量表明,这些衍生物含有配位体的三(半醌)形式配位的二价金属离子。磁数据分析表明,配体的pi连接性会增强分子的三个半醌单元之间的铁磁耦合,产生S = 9/2(M = Ni(II))和S = 6(M = Mn(II))基态的配合物。三(半醌)单元内的偶联非常大(对于镍(II)衍生物而言,J = -26 cm(-1),对于锰(II)衍生物而言,J =