Structural and dynamical properties of graphite by incorporating dispersion correction: An ab-initio study

An accurate dispersion corrected study of structural and vibrational properties of graphite using the dispersion corrected density functional theory (DFT-D) is carried out. The dispersion corrected Tkatchenko and Scheffler (TS) scheme has been implemented with generalized gradient approximation (GGA) for the exchange and correlation functional in the formalism of Perdew, Burke and Ernzerhof (PBE) in order to include the long range interactions. The structural and vibrational properties of the graphite system are improved after adding the Van der Waals interactions. The calculated low frequency dispersion corrected modes of vibration have an excellent comparison with available experimental inelastic X-ray scattering and coherent inelastic neutron scattering results.