Electrostatic bending and outer-sphere intervalence transfer in a flexible ligand-bridged ruthenium(III)-iron(II) complex. Issue 11 (3rd July 2018)

• Record Type: Journal Article
• Authors: Aguirre-Araque, Juan S.; Rocha, Reginaldo C.; Toma, Henrique E.
• Is Part Of: Journal of coordination chemistry. Volume 71:Issue 11/13(2018)
• Page Start: 1778
• Page End: 1790
• Publication Date: 2018-07-03
• Subjects: Outer-sphere intervalence transfer -- electrostatic configurational bending -- pentaammineruthenium complexes -- pentacyanidoferrate complexes -- mixed valency; Coordination compounds -- Periodicals; 541.2242
• DOI: 10.1080/00958972.2018.1493725
• Languages: English
• ISSNs: 0095-8972

Abstract

Abstract: In the mixed-valence complex [Ru III (NH3 )5 (μ-dpypn)Fe II (CN)5 ] with the flexible bridging ligand 1, 3-di(4-pyridyl)propane (dpypn), electrostatic interactions between the {Ru(NH3 )5 } 3+ and {Fe(CN)5 } 3− moieties drive a strong bending of dpypn and approximation of the Ru III and Fe II centers, from which the enhanced electronic coupling between metal ions produces an intense intervalence-transfer absorption in the near-infrared region. Density functional theory calculations corroborate both the electrostatic bending in this heterobinuclear complex and a linear geometry in the homobinuclear counterparts [Ru(NH3 )5 (μ-dpypn)Ru(NH3 )5 ] 5+ and [Fe(CN)5 (μ-dpypn)Fe(CN)5 ] 5−, for which no evidence of electronic coupling was found because of the separation between metal centers. Furthermore, the heterobinuclear species formed an inclusion complex with β-cyclodextrin where the imposed linear geometry prevents significant electronic coupling and intervalence charge transfer between the Ru III and Fe II centers. GRAPHICAL ABSTRACT: