Berlin 2018 – wissenschaftliches Programm

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MM: Fachverband Metall- und Materialphysik

MM 47: Poster Session II

MM 47.15: Poster

Mittwoch, 14. März 2018, 18:30–19:45, Poster C

Test and analysis of nonlocal van der Waals density functionals for solids — •Leila Kalantari, Fabien Tran, and Peter Blaha — Vienna University of Technology, Vienna, Austria

Recently, a scheme for the implementation of nonlocal van der Waals (NL-vdW) functionals into all-electron codes was proposed by Tran et al. [Phys. Rev. B 96, 054103 (2017)]. With this method, benchmark results can be obtained at reasonable computational time since it is based on fast Fourier transformations as proposed by Román-Pérez and Soler [Phys. Rev. Lett. 103, 096102 (2009)] after the all-electron density is smoothed. In this work, the results of a comparison of some of the most recently developed NL-vdW functionals will be presented, and the test set consists of simple cubic solids as well as several vdW bounded solids. Among the latter are some rare gases, graphite, h-BN and several transition metal dichalcogenides MX₂, where M represents transition metals and X being either S, Se or Te. We have determined the ground state geometry and interlayer binding energy of the MX₂ compounds. The calculations are done with the WIEN2k code which is based on the linearized augmented plane-wave basis set. The convergence of the results with respect to parameters like the size of the basis set, the number of k-points, the cutoff for smoothing the density and the FFT-grid will also be discussed.