- 作者: 曹蓮桂 ; 吳明珠 ; 葉玉堂
- 作者服務機構: 東海大學化學系
- 中文摘要: The pyrimidine bridged binuclear complex (CN)/sub 5/ FepymRu(NH/sub 3/)/sub 5//sup -/ (1) was prepared in aqueous solution by mixing equimolar of Fe(CN)/sub 5/ OH/sub 2//sup 3-/ and Ru(NH/sub 3/)/sub 5/pym/sup 2+/. Its mixed valence state molecule ( CN)/sub 5/FepymRu(NH/sub 3/)/sub 5/ (2) was obtained upon oxidation of (1) by one equivalent of peroxydisulfate ion. Both binuclear complexes and corresponding Fe(II) and Ru(II) mononuclear complexes displayed a metal-to-ligand charge transfer absorption in 400 to 450nm region. Rate constants of formation and dissociation of (1) and (2) were measured, and the values of k/sub f/ (.sim.10/sup 3//M-s) and k/sub d/(.sim.10/sup -3/ to 10/sup -4//s) were consistent with kinetic results expected for the substitution of Fe(CN)/sub 5/OH/sub 2//sup 3-/ with di- and trivalent ligands. Cyclic voltammetry of (1) exhibited two one-electron steps of oxidation corresponding to [ III, L, II ] + e .arrr. [ II, L, II ] and [ III, L, III ] + e .arrr. [ III, L, II ] , respectively. The mixed valence binuclear complex (2) showed an intervalence band at 955nm with a molar extinction coefficient 5.80*10/sup 2//M-cm and a half-width 5100/cm. The properties of the IT band conform to Hush's theory. Spectroscopic, electrochemical and kinetic results of (2) suggest that the mixed valence complex features a trapped-valence formulation with localized oxidation states of Fe(II) and Ru(III).
- 英文摘要: --
- 中文關鍵字: Mixed Valence; Hush's Theory; Intervalence Band; Ion Pair Formation Constant; Bridged Binuclear Complex
- 英文關鍵字: 混合共價;Hush理論;內共價帶;離子對生成常數;架橋雙核錯合物