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O: Fachverband Oberflächenphysik
O 10: Methods: Electronic structure theory & Methods: other (theory)
O 10.3: Vortrag
Montag, 22. März 2010, 15:30–15:45, H31
Using the kinetic energy density in local density functionals — •Georg Madsen1, Lara Ferrighi2, and Bjork Hammer2 — 1ICAMS, Ruhr Universität Bochum, Germany — 2Department of Physics and Astronomy, Aarhus University, Denmark
Recent developments in local functionals including the
kinetic energy density, so-called meta-generalized gradient approximations
(MGGAs), are described. It is shown how MGGAs can solve the long-standing
problem of the cross over between 2D and 3D structure for cationic and anionic
gold clusters. The MGGAs stronger tendency towards 3D structures lies in their
smaller gradient enhancement, but contrary to GGAs with smaller gradient
enhancements, MGGAs do not overestimate the atomization energy. Furthermore,
we find that closed shell interactions are fingerprinted in the kinetic
energy density and that MGGAs have enough flexibility to treat correctly both the covalent and the
dispersive interactions in layered solids such as Graphite, h-BN and MoS2.
It is shown how MGGAs thereby potentially can give a
consistent improvement over the GGAs for the adsorption on metal surfaces.
Ferrighi, Hammer, Madsen, J. Am. Chem. Soc. 2009, 131, 10605
Madsen, Ferrighi, Hammer, J. Phys. Chem. Lett.