Hyperpolarizability calculations for dye-sensitized solar cell materials

In this thesis, the structural and electronic properties for the different conformers of a sensitizing material in dye-sensitized solar cells have been investigated. Calculations have been carried out by approaches including quantum mechanical modeling methods. The calculated highest occupied orbital and lowest unoccupied orbital energy levels of the structures have been compared with the energy level of the redox couple of the iodide electrolyte and the conduction band energy level on the titanium dioxide surface, respectively. In addition, static and frequency-dependent hyperpolarizability calculations have been made for the sensitizer conformers. In the calculation results, the average polarizabilities have the order of C1>C3>C2 in static values, while the other static and frequency-dependent polarizability and hyperpolarizability calculations at λ=532.2 nm are in the order of C1>C2>C3. The larger values in static and frequency-dependent dipole polarizability, hyperpolarizability have been obtained at lower energy band gaps of the structures.