Publication Details
Abstract
The presents research focuses on a theoretical study of structural and electronic properties of pure graphene sheet and then adding different number of N2 atoms . The calculations are carried out using the density functional theory(DFT) was used with hybrid functional B3LYP/6-31G level of theory to investigate the proposed structures. Gauss View 5.0.8 program was used to design the structures of pure and doped graphene sheets. These structures are relaxed by employing the PM6 semi- empirical method with the hybrid functional B3LYP-DFT at Gaussian 09 package of programs. The results of the structural properties of the studied graphene sheets observed that good relaxation of the structures, the values of C-C,C=C, C⚍C and C-H bonds in pure graphene sheets remain in the same ranges of the carbon rings structures . These calculations are included the total energy, High Occupied Molecular Orbital HOMO and Low Unoccupied Molecular Orbital LUMO energies, forbidden energy gap, ionization energy and electron affinity, electrochemical hardness, electronic softness. The result of the total energy of the studied doping graphene sheets is a reflection of the binding energy of each structure and indicates to that these structures have good relaxation, and the effect of adding N2 atoms in pure graphene sheet on the total energy of the molecule is effective. We showed all doping graphene sheets have small forbidden energy gap, but it vibrates depending on the length and number of each sheet and position of N2 atoms in the sheets. The ionization energy IE and electron affinity EA of the doping graphene sheets are slightly decrease with decreasing the length of the sheets. And all doped graphene sheets have low values of IE and EA in comparison with the pure. Also, we showed that all the pure and doped graphene sheets have low electrochemical hardness H and high electronic softness S. High electronic softness is the main future as a sign for that band gap of the structure goes to be rather soft.