School of Chemistry, Bharathidasan University, Tiruchirappalli 620 024, India.
Spectrochim Acta A Mol Biomol Spectrosc. 2014 Jan 3;117:138-43. doi: 10.1016/j.saa.2013.07.040. Epub 2013 Aug 8.
Synthesis of several new octahedral binuclear ruthenium(III) complexes of the general composition [(EPh3)2(X)Ru-L-Ru(X)(EPh3)2] containing benzene dithiosemicarbazone ligands (where E=P or As; X=Cl or Br; L=binucleating ligands) is presented. All the complexes have been fully characterized by elemental analysis, FT-IR, UV-vis and EPR spectroscopy together with magnetic susceptibility measurements. IR study shows that the dithiosemicarbazone ligands behave as dianionic tridentate ligands coordinating through the oxygen atom of the deprotonated phenolic group, nitrogen atom of the azomethine group and thiolate sulphur. In DMF solution, all the complexes exhibit intense d-d transition and ligand-to-metal charge transfer (LMCT) transition in the visible region. The magnetic moment values of the complexes are in the range 1.78-1.82 BM, which reveals the presence of one unpaired electron on each metal ion. The EPR spectra of the liquid samples at LNT show the presence of three different 'g' values (gx≠gy≠gz) indicate a rhombic distortion around the ruthenium ion. All the complexes exhibit two quasi-reversible one electron oxidation responses (Ru(III)-Ru(III)/Ru(III)-Ru(IV); Ru(III)-Ru(IV)/Ru(IV)-Ru(IV)) within the E1/2 range of 0.61-0.74 V and 0.93-0.98 V respectively, versus Ag/AgCl.
合成了几种新的八面体双核钌（III）配合物，其通式为[(EPh3)2(X)Ru-L-Ru(X)(EPh3)2]，其中 E 为 P 或 As；X 为 Cl 或 Br；L 为双核配体，含有苯二硫代缩氨基脲配体。所有配合物均通过元素分析、FT-IR、UV-vis 和 EPR 光谱以及磁化率测量进行了充分表征。IR 研究表明，二硫代缩氨基脲配体作为阴离子三齿配体，通过酚基去质子化的氧原子、亚氨基氮原子和硫醇硫原子配位。在 DMF 溶液中，所有配合物在可见光区均表现出强烈的 d-d 跃迁和配体到金属电荷转移（LMCT）跃迁。配合物的磁矩值在 1.78-1.82 BM 范围内，表明每个金属离子上有一个未成对电子。在 LNT 下的液体样品的 EPR 光谱显示存在三个不同的'g'值（gx≠gy≠gz），表明钌离子周围存在菱形畸变。所有配合物均在 E1/2 范围内表现出两个准可逆的单电子氧化响应（Ru(III)-Ru(III)/Ru(III)-Ru(IV)；Ru(III)-Ru(IV)/Ru(IV)-Ru(IV)），分别为 0.61-0.74 V 和 0.93-0.98 V，相对于 Ag/AgCl。
