| dc.description.abstract | Band structures are very important in understanding the electronic structure of materials; as a result, a good methodology for finding the band structure for electronic materials is extremely important. Organic materials are focused on since their electronic structure is not as extensively researched. This research is purely computational, using molecular editing programs like Avogadro to model the organic semiconductors used and, Quantum Espresso to run all the calculations needed to find the band structure. Quantum Espresso uses density functional theory to calculate the wave functions and band structures for the organic semiconductors, and the program GNUplot is used to plot those band structures. Eight organic semiconductors are screened, while only three have had their band structure calculated. These three molecules are TTT-I3, TTF-TCNQ, and Pentacene. Their respective fermi energies are -0.88114 eV, -0.5583 eV, and 0.1890 eV. The band gaps for TTT-I3 and Pentacene that were calculated were 1.1507 eV and 0.141149 eV while TTF-TCNQ did not give a band gap in relation to the fermi energy. The results for the band structures were initially calculated over a symmetric wedge of the brillouin zone, so a new k-point path specific band structure was needed to be calculated in order to get a more accurate band gap for all the organic semiconductor molecules. Even though the band structures were initially not over a specific k-point path, the calculation still provided an estimate on the band gap. This research is a stepping stone for future work on calculating the band structure for organic semiconductors, and hopefully one day will provide a good methodology for calculating the band structure for any organic material. | |
