Electrochemical studies of mixed-ligand complexesof rhodium(III) containing N,N'–dipyridylamine

• Main Authors: Jen-Hsing Huang, 黃任興
• Other Authors: Wen-Liang Huang
• Format: Others
• Language: zh-TW
• Published: 2002
• Online Access: http://ndltd.ncl.edu.tw/handle/98299401685896308629

碩士 === 國立成功大學 === 化學系碩博士班 === 90 === Abstract Cyclic voltametric data have been obtained for mixed-ligand complexes of rhodium(III) containing N,N'–dipyridylamine，cis-[Rh(L-L)(HDPA)Cl2]Cl、cis-Rh(L-L)(DPA)Cl2（L-L=bipy or phen）and cis-[Rh(HDPA)2Cl2]Cl in acetonitrile. For cis-[Rh(L-L)(HDPA)Cl2] Cl，between 0∼+1.80 V vs. SCE there is a reversible oxidation peak which is +1.07∼+1.08 V and reduction peak is +0.85∼+0.87 V. This is attributed to oxidation of chloride ion. There are two irreversible reduction peaks between 0∼-1.80 V vs. SCE. Each of the reductions is one-electron reduction step followed by fast elimination of a chloride which is consistant with an ECEC（E：electron transfer，C：chemical reaction）mechanism. One can therefore suggest that their redox orbitals are assigned to be metal-localized. The luminescence had been suggested as πd* for cis-Rh(L-L)(DPA)Cl2. In electrochemical studies of these complexes，there is no peak observed between 0∼+1.80 V vs. SCE and only one irreversible reduction peak observed between 0∼-1.80 V vs. SCE. This reduction is one-electron reduction step followed by elimination of a chloride，which assigns that complexes belong to πd* transition. For cis-[Rh(HDPA)2Cl2]Cl，between 0∼+1.80 V vs. SCE there is a reversible oxidation peak which is +1.08 V and reduction peak is +0.89 V. This is attributed to oxidation of chloride ion. There is one irreversible reduction peak between 0∼-1.80 V vs. SCE. This reduction peak including two reduction steps followed by fast elimination of a chloride is consistent with an ECEC reaction. Therefore，the redox orbitals are also assigned to be metal-localized.