Abstract: A theme of the present invention is to provide a new transition metal complex, useful as a photosensitizer dye for a photoelectric conversion element having an excellent durability and a high photoelectric conversion characteristic. The present invention provides a bivalent transition metal complex constituted of (i) a bipyridyl polyacidic ligand, such as a dicarboxybipyridyl (dcbpy) ligand, as an adsorption site for adsorption onto titanium dioxide particle surfaces; (ii) a ligand, selected from the group consisting of an isothiocyanato group, an isocyanato group, and an isoselenocyanato group and enabling absorption and excitation at long wavelengths and charge transfer; and (iii) a bipyridyl (bpy) ligand, having an alkyl group or an alkoxy group, preferably a long-chain alkyl group, and a conjugately bonded thienylvinylene group, aminophenylenevinylene group, etc.

Abstract: A theme of the present invention is to provide a new transition metal complex, useful as a photosensitizer dye for a photoelectric conversion element having an excellent durability and a high photoelectric conversion characteristic. The present invention provides a bivalent transition metal complex constituted of (i) a bipyridyl polyacidic ligand, such as a dicarboxybipyridyl (dcbpy) ligand, as an adsorption site for adsorption onto titanium dioxide particle surfaces; (ii) a ligand, selected from the group consisting of an isothiocyanato group, an isocyanato group, and an isoselenocyanato group and enabling absorption and excitation at long wavelengths and charge transfer; and (iii) a bipyridyl (bpy) ligand, having an alkyl group or an alkoxy group, preferably a long-chain alkyl group, and a conjugately bonded thienylvinylene group, aminophenylenevinylene group, et.