Investigation of the electron transfer properties between metal centers in binuclear and trinuclear cyanido-bridged mixed valence complexes with cis / trans -configuration.

To investigate the electron transfer properties between metal centers and their influencing factors in binuclear and trinuclear cyanido-bridged mixed valence complexes with cis / trans -configuration, binuclear cis -[Cp(dppe)Fe(μ-NC)Ru(5,5'-dmbpy) 2 (μ-CN)][PF 6 ] n (cis-1[PF6]n, n = 1, 2) and trinuclear cis / trans -[Cp(dppe)Fe(μ-NC)Ru(5,5'-dmbpy) 2 (μ-CN)Fe(dppe)Cp][PF 6 ] n (cis/trans-2[PF6]n, n = 2, 3, 4) (Cp = 1,3-cyclopentadiene, dppe = 1,2-bis(diphenylphosphino)ethane, 5,5'-dmbpy = 5,5'-dimethyl-2,2'-bipyridyl) cyanido-bridged complexes were synthesized and well characterized. The experimental results indicate that the presence of the other terminal fragment Cp(dppe)Fe III in cis-2[PF6]4 results in higher MMCT energy than that of cis-1[PF6]2. In addition, the trans -configuration is more conducive to electron transfer between metal centers than the cis -configuration in trinuclear cyanido-bridged mixed valence complexes. Moreover, these mixed valence complexes cis-1[PF6]2 and cis/trans-2[PF6]n ( n = 3, 4) could be assigned to Class II systems according to Robin and Day.