Van der Waals interactions based on maximally localized Wannier functions in ABINIT

We review the recent implementation\footnote{C. Espejo et al. Computer Phys. Comm. In press (2011), doi:10.1016/j.cpc.2011.11.003} of the method to evaluate van der Waals (vdW) interactions based on maximally localized Wannier functions\footnote{P. L. Silvestrelli. Phys. Rev. B., \textbf{100}, 053002 (2008)}$^,$\footnote{P. L. Silvestrelli. J. Phys. Chem. A., \textbf{113}, 5224 (2009)} in the DFT software ABINIT\footnote{X. Gonze et al. Computer Phys. Comm. \textbf{180}, 2582 (2009)}. The implementation allows for the evaluation of vdW interaction energies for molecular and periodic systems on the same grounds and at a low additional computational cost as compared with a normal DFT calculation. Some results on test systems such as Ar$_2$, benzene dimer and graphene bilayer show both its reliabilty and performance. Discussion of new defined variables controlling the calculation and guide lines for the user will be presented along with an application to MoS$_2$ structure.