Which technique was used to get the dispersion diagram (in 3D) of graphene which shows 6 dirac points in the first brilluion zone?
Dispersion digram is the two dimensional plot of energy versus k points. It provide you the information about the electronic structure. In general there are several density functional based codes available. You can try either one, but, keep in mind that the type of electron interaction is taken care in the estimation of the dispersion plot. I recommend to use the all electron codes such as implented in Wien2k code (it's paid code), or you can try ELK-Lapw code (it's free). If you want to make quick calculations you can try with psuedopotential based code such as quantum espresso or VASP code. The dispersion plot is need to done along the high symmetric points in the Brilluion zone. You can get easily the Dirac points. The three dimensional view can be visualised by calculations of Fermi surface. Best wishes.
. Results for graphene In the calculation of the phonon-dispersion relation of graphene done by Saito et al., 38 the force-constant parameters were empirically determined by fitting experimental data of graphite obtained by inelastic neutron scattering. We perform, instead, a parameter fit to the ab initio dispersion relation of graphene calculated within density-functional perturbation theory by Bohnen and Heid.49 The corresponding sets of force constants are listed in Table I. Precisely, the fitting process was performed through a matching of the force-constant tensor to those obtained by ab initio calculations.49 This procedure is however limited by the constraint of including up to fourth nearest neighbors in the force-constant tensor, as required by the model approach. We varied and optimized the force constants in order to fit as closely as possible the ab initio phonon dispersion. We follow Gartstein52 choos
- Badges
- Science topic
- Similar topics
- Physical Sciences
- Materials Science
- Materials
- Carbon Materials
- Graphite
- Graphene