The electronic structure of the cis-bis(4,4'-dicarboxy-2,2'-bipyridine)-bis(isothiocyanato) ruthenium(II) complex and its ligand 2,2'-bipyridyl-4,4'-dicarboxylic acid studied with electron spectroscopy

The electronic structure of the dye complex cis-bis(4,4'-dicarboxy-2,2'-bipyridine)-bis(isothiocyanato)ruthenium(II) as well as that of its ligand 2,2'-bipyridine-4,4'-dicarboxylic acid has been investigated with electron spectroscopy. Valence level spectra have been studied with respect to photoelectron angular distributions and photon energy dependence. The experimental information coupled with semi-empirical INDO/S calculations provides a mapping of the orbital parentage of the dye complex and its ligands, The energy levels of the dye complex in the context of a sensitized semiconductor (nanostructured titanium dioxide) surface are related to the bands of the semiconductor. (C) 1997 Elsevier Science B.V.