A theoretical study on charge transfer and other properties induced by conformation conversion of ligands in Ru complexes

第二排过渡金属络合物表现出比第一排过渡金属络合物更高的共价性，并显示出有趣的化学性质。在本研究中，我们选取了含Ru(相当于Fe)的配合物，主要研究了[Ru(III)L_5NO]^&lt；2-&Gt；和Ru_3O(CH_3CO_2)_6L_2CO的电子结构。这些材料在过渡金属络合物领域受到了特别的关注，并试图在生物或电子学以及基础研究领域发展它们。这类配合物表现出由配体的电荷转移和构象转换引起的独特性质：[Ru(III)L_5NO](L=CN^-)；该配合物的晶体具有两个极长寿命的光致亚稳态。这有望成为一种很有前途的开关材料。在本研究中，我们用从头算…方法研究了[Fe(III)L_5NO]和[Ru(III)L_5NO]的基态和两个亚稳态的结构以及它们之间的势垒高度更多的祝贺。此外，还计算了整体激发态势能面，并解释了亚稳态和基态之间可能通过非绝热跃迁而发生的光致异构化。Ru3O(CH3CO2)6L2CO(L=bzpy)，[Ru(CH3CO2)6(Bzpy)2CO]n(n=-2~0，bzpy=4-苯甲酰基吡啶)的电子结构和相对稳定性。最近，Tanaka et al.报道了该络合物Ru_3O(CH_3CO_2)_6L_2CO的六个单电子可逆氧化还原过程。在他们的工作中，只有该络合物的两个电子还原物种在CH2Cl2溶液中获得了两个略有不同的C-O振动频率，而在其他物种中只有一个C-O振动模式。这表明在二次还原的异构体中存在两种类型的异构体。在目前的计算中，我们发现在Ru_3-O平面和bzpy平面之间的二面角上的整体最小值几乎是90°(垂直)。平面结构(0,180°)为局部极小值。对于两个电子还原物种，在平面结构和垂直结构存在两个极小值，它们的总能量彼此接近。这似乎解释了两种不同的C-O振动模式。较少

The second row transition metal complexes show higher covalency than the first row transition metal complexes, and exhibit chemically interesting properties. In this study, we take complexes including Ru which is equivalent to Fe and investigate electronic structures of primarily [Ru(III)L_5NO]^<2->, and Ru_3O(CH_3CO_2)_6L_2CO. These materials have been paid special attention in the field of transition metal complexes and tried to develop them in the biological or electronics as well as subject of fundamental studies. These types of complexes show unique properties induced by charge transfer and conformation conversion of ligands.[Ru(III)L_5NO] (L=CN^-) ; The crystal of this complex has two extremely long-lived photo-induced meta stable states. This is expected to be a promising switching material. In this study, we took [Fe(III)L_5NO] as well as [Ru(III)L_5NO] and studied the structure of the ground state and two meta stable states, and barrier heights among them, using ab initio calc … More ulations. Further more global excited state potential surfaces were calculated and explained possible photo induced isomerization among the meta stable and ground states by non-adiabatic transition. The high covalency in Ru complex cause higher potential barrier than in Fe complex and it is the origin of the longer life-time in Ru complex than in Fe complex.Ru_3O (CH_3CO_2)_6L_2CO (L=bzpy) ; We reported the electronic structure of [Ru_3O(CH_3CO_2)_6(bzpy)_2CO]^n (n=-2〜0, bzpy=4-benzoylpyridine) and relative stability of the isomers, using results of ab initio molecular orbital calculations. Recently, Tanaka et al. reported that the complex, Ru_3O(CH_3CO_2)_6L_2CO, shows six one-electron reversible redox processes. In their work, two slightly different C-O vibrational frequencies were obtained only for the 2 electron reduction species of this complex in CH_2Cl_2 solution, whereas only one C-O vibrational mode in the other species. This suggests that there exists two types of isomers in doubly reduced one. In the present calculation, we found the global minimum at the dihedral angle between the Ru_3-O plane and bzpy plane was almost 90° (perpendicular). The planer structure (0, 180°) was the local minimum. For the 2 electron reduction species, there were two minima at a planer structure and a perpendicular structure whose total energies are close to one another. This seems to explain the two C-O different vibrational modes. Less