Multiple MMCT properties of the diruthenium-based cyanido-bridged complex RuVI2-NC-RuII-CN-RuVI2

Dalton Trans. 2022 Jul 5;51(26):10047-10054. doi: 10.1039/d2dt00408a.

Abstract

The diruthenium-based linear mixed valence complex trans-[Ru2(ap)4-NC-Ru(DMAP)4-CN-Ru2(ap)4][PF6]2 (12+[PF6]2) (ap = 2-anilinopyridinate, DMAP = 4-dimethylaminopyridine) and its two-electron oxidation product 14+[PF6]4 have been synthesized and fully characterized. The investigation reveals that complex 12+ displays a single MMCT transition, whereas complex 14+ has three identified MMCT transitions (MMCT-1, MMCT-2 and MMCT-3) upon oxidation. Interestingly, MMCT-2 in complex 14+ might result from the transition from the RuIII-NC-RuII-CN-RuIII component, which is composed of the central RuII and its two neighboring RuIII atoms from the cluster RuVI2 units, to both the terminal RuIII atoms of the same cluster RuVI2 units, which is supported by the TDDFT calculations.