A novel ruthenium surfactant: electronic spectra, ZINDO analysis and Langmuir-Blodgett studies of trans-dichloro(6,6 '-bis(N-dodecylbenzimidazol-2-yl)-2,2 '-bipyridine)ruthenium(II)

Citation
Mf. Ryan et al., A novel ruthenium surfactant: electronic spectra, ZINDO analysis and Langmuir-Blodgett studies of trans-dichloro(6,6 '-bis(N-dodecylbenzimidazol-2-yl)-2,2 '-bipyridine)ruthenium(II), J CHEM S DA, (14), 2000, pp. 2357-2365
Citations number
116
Categorie Soggetti
Inorganic & Nuclear Chemistry
Journal title
JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS
ISSN journal
1470479X → ACNP
Issue
14
Year of publication
2000
Pages
2357 - 2365
Database
ISI
SICI code
1470-479X(2000):14<2357:ANRSES>2.0.ZU;2-0
Abstract
The complex, dichloro(6,6'-bis(N-dodecylbenzimidazol-2-yl)-2,2'-bipyridine) ruthenium(II), Ru(ddbbbpy)Cl-2 was prepared from the reaction of the free l igand and RuCl2(Me2SO)(4). Structural characterization of the compound by H -1 NMR revealed that 6,6'-bis(N-dodecylbenzimidazol-2-yl)-2,2'-bipyridine l igand lies symmetrically about the equatorial plane with the chlorides axia l to each other. The electronic structure of the compound shows several lig and pi-pi* transitions in the ultraviolet and a broad d(pi)-p(pi*) MLCT man ifold in the visible region of the spectrum. A ZINDO/S calculation reproduc es, in some detail, the general features of the electronic spectrum of the title species. The electronic characteristics of the frontier orbitals are analysed. The parent neutral compound shows a fully reversible oxidation wa ve at -0.04 V vs. the Cp2Fe+/Cp2Fe couple in 0.1 M (C4H9)(4)NPF6/CH2Cl2. Th e low temperature (77 K) EPR spectrum of the one-electron oxidized product is typical for a rhombohedrally distorted Ru(III) complex with g values of 2.73, 2.20 and 1.82. Surface analysis of the parent complex as studied usin g Langmuir-Blodgett methods show a typical isotherm from which an area per molecule of 126 Angstrom(2) can be derived. Thin films of the complex were readily transferred to quartz and indium doped tin oxide (ITO) plates. Thin films are conductive as indicated by the cyclic voltammetry of the complex es on ITO slides.