Bengt I Lundqvist

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It is shown that it is now possible to include van der Waals (vdW) interactions via a nonempirical implementation of density functional (DF) theory to describe the correlation energy in electronic structure calculations on infinite systems of no particular symmetry. The vdW-DF theory [Phys. Rev. Lett. 92, 246401 (2004)] is applied to the adsorption of(More)
Sparse matter is abundant and has both strong local bonds and weak nonbonding forces, in particular nonlocal van der Waals (vdW) forces between atoms separated by empty space. It encompasses a broad spectrum of systems, like soft matter, adsorption systems and biostructures. Density-functional theory (DFT), long since proven successful for dense matter,(More)
First-principles calculations of phenol adsorbed on two different surfaces, graphite͑0001͒ and ␣-Al 2 O 3 ͑0001͒, are performed with traditional semilocal density functional theory ͑DFT͒ and with a recently presented density functional ͑vdW-DF͒ that incorporates the dispersive van der Waals ͑vdW͒ interactions ͓Phys. Rev. Lett. 92, 246401 ͑2004͔͒. The vdW-DF(More)
A scheme within density functional theory is proposed that provides a practical way to generalize to unrestricted geometries the method applied with some success to layered geometries [Phys. Rev. Lett. 91, 126402 (2003)]]. It includes van der Waals forces in a seamless fashion. By expansion to second order in a carefully chosen quantity contained in the(More)
We propose a second version of the van der Waals density functional of Dion et al. ͓Phys. Rev. Lett. 92, 246401 ͑2004͔͒, employing a more accurate semilocal exchange functional and the use of a large-N asymptote gradient correction in determining the vdW kernel. The predicted binding energy, equilibrium separation, and potential-energy curve shape are close(More)
To understand sparse systems, we must account for both strong local atom bonds and weak nonlocal van der Waals forces between atoms separated by empty space. A fully nonlocal functional form [Phys. Rev. B 62, 6997 (2000)]] of density-functional theory (DFT) is applied here to the layered systems graphite, boron nitride, and molybdenum sulfide to compute(More)
The details of a density functional that includes van der Waals (vdW) interactions are presented. In particular we give some key steps of the transition from a form for fully planar systems to a procedure for realistic layered compounds that have planar symmetry only on large-distance scales, and which have strong covalent bonds within the layers. It is(More)
There was an error in transcribing Fig. 1 into the variables and D. These variables were not contained in the code used in the calculations, and our results were not affected. A corrected version of Fig. 1 is included with this erratum. We thank Jesper Kleis for discovering this error. The new figure also contains small corrections resulting from an(More)
Atoms and molecules adsorbed on metals affect each other indirectly even over considerable distances. Via systematic density-functional calculations, we establish the nature and strength of such interactions, and explain for what adsorbate systems they critically affect important materials properties. This is verified in kinetic Monte Carlo simulations of(More)
The theoretical description of sparse matter attracts much interest, in particular for those ground-state properties that can be described by density functional theory. One proposed approach, the van der Waals density functional (vdW-DF) method, rests on strong physical foundations and offers simple yet accurate and robust functionals. A very recent(More)