EVALUATION OF THE TOTAL AND PROJECTED DENSITY OF STATE OF TETRACENE MOLECULE IN THE PRESENCE OF PHENYL RINGS

In this article, we investigate the total and projected density of state for adding four phenyl rings on different position of tetracene molecule by using density functional theory with SIESTA code. Also, we found that, the most contribution of atomic states in the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) are due to the p orbitals of carbon atoms. Moreover, our results clearly show that carbons on phenyl rings do not have any significant influence on the contributions of carbon atoms in HOMO and LUMO peaks and like tetracene the most contributions belong to tetracene backbone. Furthermore, Phenyl groups cause to reduce the value of HOMO- LUMO gap that has important effect on electronic properties of molecule. Moreover, it cause to shift the position of HOMO and LUMO peaks.