DFT Calculations of IR and Raman Spectra of Ru(bpy)2(CN)2 Complex

Harvesting energy directly from sunlight using photovoltaic technology is an essential component of the future global energy production programs [1]. Photovoltaic devices, or solar cells, are based on the photoelectric effect, in which the incoming solar photons are absorbed in a sensitized semiconductor material freeing electric charges that are used to energize an external circuit [2]. The solar cells on the bases of nanocrystalline TiO2 are usually sensitized by metal-organic dyes such as Rucomplexes with phenylpyridine and bipyridine ligands. The incident photon to current conversion efficiency (IPCCE) in the wavelength region 400-600 nm can be rather high [1, 2]. In order to improve the IPCCE value the heavier metal ions could be tested. Such sensitizers as coumarin, porphyrins, chlorophyll derivatives, antennasentsitizer polynuclear complexes and eosin have been studied and reported to be less efficient than the most effective Ru-based sensitizing dyes, called the black dye (BD) and N3 dye [2–4], used for the nanocrystalline TiO2 solar cell. In this paper we are planning to understand the IPCE of a new dye-sensitizer in order to predict the higher absorption efficiency to solar spectrum and higher electron transfer rate from redox systems to oxidized dye. Some simple Ru(II)(bpy)2(CN)2 complex is studied by DFT method with optimized structure and vibrational analysis in order to predict the role of vibronic perturbations in spectra and interface electron transfer rate.