A new strategy for inducing dipole moments in charge-transfer complexes: Introduction of asymmetry into axially ligated iron phthalocyanines
A new strategy for inducing dipole moments in charge-transfer complexes: Introduction of asymmetry into axially ligated iron phthalocyanines
复制标题
在电荷转移复合物中诱导偶极矩的新策略：在轴向连接的铁酞菁中引入不对称性
DOI：
10.1039/c7dt02605f
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发表时间：
2017
影响因子：
4
通讯作者：
N. Hanasaki
中科院分区：
文献类型：
--
作者：
M. Matsuda,* S. Iwamura;Y. Hamada;H. Ohishi;M. Nishi;Y. Nogami;M. Ikeda;A. Kanda;Y. Funasako;T. Mochida;A. Nakao;N. Hanasaki
实现了轴向配位铁酞菁电荷转移配合物的不对称引入。在所获得的TPP[FeIII（Pc）（CN）Cl]2、TPP[FeIII（Pc）（CN）Br]2和TPP[FeIII（Pc）BrCl]2（TPP =四苯基鏻和Pc =酞菁）的晶体中，铁原子的轴向位置分别被50/50比率的配体CN/Cl、CN/Br和Br/Cl占据。CT配合物的晶体结构与[Fe III（Pc）L2]（L = CN，Cl或Br）型对称类似物的晶体结构相同，[Fe III（Pc）LL′]单元沿着c轴形成规则的一维链状结构，遵循P42/n空间群的对称性。尽管形成类似的规则链的对称系统，在所获得的CT复合物的电介电常数和活化能的增强相比，那些在对称系统中，表明电荷有序状态的不对称性的引入是稳定的。更具体地说，介电弛豫行为的非均匀无序TPP[FeIII（Pc）（CN）Cl]2可能表明，在这种材料中诱导的偶极矩。
Introduction of asymmetry into charge-transfer complexes composed of axially ligated iron phthalocyanines was achieved. In the obtained crystals of TPP[FeIII(Pc)(CN)Cl]2, TPP[FeIII(Pc)(CN)Br]2, and TPP[FeIII(Pc)BrCl]2 (TPP = tetraphenylphosphonium and Pc = phthalocyanine), the axial positions of the iron atoms were occupied by 50/50 ratios of the ligands CN/Cl, CN/Br, and Br/Cl, respectively. The crystal structures of the obtained CT complexes were isostructural to those composed of the symmetric analogues of the type [FeIII(Pc)L2] (L = CN, Cl or Br); the [FeIII(Pc)LL′] units formed regular one-dimensional chains along the c-axis following the symmetry of the P42/n space group. Despite forming similar regular chains to the symmetric systems, the electrical resistivities and activation energies were enhanced in the obtained CT complexes compared to those in symmetric systems, indicating that the charge-ordered states were stabilised by the introduction of asymmetry. More specifically, the dielectric relaxation behaviour of the inhomogeneous disordered TPP[FeIII(Pc)(CN)Cl]2 probably suggests that a dipole moment was induced in this material.