| Organic semiconductors have received a great deal of attention in recent years due to their optoelectronical properties and their potential applications in industry. In this thesis, resonance Raman calculations of a family of organic semiconductor dyes: perylene tetracarboxylic diimides (PTCD) derivatives, are presented. Also the UV/vis, infrared and normal Raman spectra, structures and molecular orbitals, excitation energies, dipole moments, (hyper) polarizabilities and charge population analyses of these molecules are calculated. The calculations in this thesis are performed using a Time-Dependent Density Functional Theory (TDDFT) method, and for that, the Amsterdam Density Functional program package (ADF2009) is used. The molecular properties calculated for the molecules in this thesis are then compared with experimental data and the main spectroscopic characteristics are found to be, for the most part, due to the perylene plane and therefore, the same for all of its derivatives.;A theoretical treatment of Raman scattering and computational chemistry methods are also reviewed in this thesis. |
