Absorption and electrochemical properties of ruthenium(II) dyes, studied by semiempirical quantum chemical calculations

• Published in: Journal of photochemistry and photobiology. A, Chemistry. Chemistry., 1998-04, Vol.114 (2), p.117-124
• Main Authors: Rensmo, Håkan, Lunell, Sten, Siegbahn, Hans
• Format: Article
• Language: English
• Subjects: Atomic and molecular physics; Calculations and mathematical techniques in atomic and molecular physics (excluding electron correlation calculations); Electronic structure of atoms, molecules and their ions: theory; Exact sciences and technology; INDO; Physics; Ru-polypyridine complex; Ruthenium; Semi-empirical and empirical calculations (differential overlap, hückel, ppp methods, etc.); Semiempirical quantum chemical calculations; Statistical model calculations (including Thomas-Fermi and Thomas-Fermi-Dirac models)
• ISSN: 1010-6030; 1873-2666
• DOI: 10.1016/S1010-6030(98)00217-2

The electronic properties of Ru-polypyridine dyes were investigated by means of semiempirical calculations. Inlermediate neglect of differential overlap (INDO)/S including configuration interaction (CI) was used to calculate electronic density of state (DOS) structures, transition energies and oscillator strengths. Results for electronic transitions and HOMO energies were compared to absorption spectra and oxidation potentials. The carboxylated form of cis-bis(2,2′-bipyridine)bis(isothiocyanato)-ruthenium(II) is an efficient sensitizer in nanos-tructured photoelectrochemical solar cells. The calculation on this dye reveals a different electronic structure for this complex compared to the other Ru-polypyridine complexes. In this complex, the spatial distribution of the highest occupied molecular orbital is shifted towards the NCS ligands and the electronic transition lowest in energy is assigned to a RuNCS-bpγ(π *) charge transfer transition.