Role and effective treatment of dispersive forces in materials: Polyethylene and graphite crystals as test cases

Abstract

A semiempirical addition of dispersive forces to conventional density functionals (DFT-D) has been implemented into a pseudopotential plane-wave code. Test calculations on the benzene dimer reproduced the results obtained by using localized basis set, provided that the latter are corrected for the basis set superposition error. By applying the DFT-D/plane-wave approach a substantial agreement with experiments is found for the structure and energetics of polyethylene and graphite, two typical solids that are badly described by standard local and semilocal density functionals.

Absorption and diffusion of beryllium in graphite, beryllium carbide formation investigated by density functional theory

“…In a number of previous works, 14,15 the interaction of beryllium with graphitic systems was investigated by DFT with the PBE functional. 18 In line with these authors, and including the van der Waals interaction in graphite according to the work of Barone et al, 19 all the calculations were performed with the Perdew-Burke-Ernzerhof generalized gradient approximation of the exchange and correlation functional, complemented by the Grimme correction DFT-D2. 20 The same methodology was carried on in a previous study.…”

Layers dependent dielectric properties of two dimensional hexagonal boron nitridenanosheets

“…16,17,32,33 The structure is relaxed completely with Van der Waals correction (dft-d2) before phonon calculations with the force threshold of 10 -6 Ry/bohr. [34][35][36][37] The accuracy test is performed through calculating the anisotropic dielectric constants of bulk h-BN depending on present method and indicates that more accurate results can be obtained by, where the results for out of plane (ε ∞ z and ε 0 z ) are very close to experimental results and that for in plane (ε ∞ ⊥z and ε 0 ⊥z ) are no larger than 6.5% (Table I). Through the DFPT calculations, the electronic permittivity of the monolayer(1L) are ε ∞ z = 5.37 and ε ∞ ⊥z = 1.82.…”

Barrier height formation in organic blends/metal interfaces: Case of tetrathiafulvalene-tetracyanoquinodimethane/Au(111)

“…32 For this purpose, we have used the revised version of the generalized gradient corrected approximation of Perdew, Burke, and Ernzerhof (rPBE), 33 and an empirical efficient van der Waals (vdW) R −6 correction to add dispersive forces to conventional density functionals (DFT − D). 34 In this method, the vdW correction is added to the DFT total energy by the expression…”