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MM: Fachverband Metall- und Materialphysik

MM 41: Poster SYM Hydrogen in Materials: New Developments

MM 41.1: Poster

Donnerstag, 28. Februar 2008, 18:00–20:00, Poster B

Beyond the featureless particle approximation: An extension of quantum-liquid density-functional theory to account for rotational effects. — •Sergei Yurchenko¹, Serguei Patchkovskii², Thomas Heine¹, and Gotthard Seifert¹ — ¹Institut für Physikalische Chemie und Elektrochemie, TU Dresden, D-01069 Dresden, Germany — ²Steacie Institute for Molecular Sciences, NRC Canada, 100 Sussex Drive, Ottawa, Ontario, K1A 0R6 Canada

In a different contribution we present QLDFT (Quantum Liquid Density Functional Theory), a Kohn-Sham based extension to DFT for liquids, to describe the adsorption properties of molecules in host structures under consideration of quantum effects. In QLDFT the individual molecules are treated as featureless particles, and rotational contributions to the free energy are neglected. However in the vicinity of strong charges the featureless particle approximation breaks down and rotational contributions become important even at ambient conditions.

We present an extension of QLDFT to account for rotational effects. Then, we apply this new method to examine the effect of electric field-induced interactions on hydrogen adsorption. These interactions initiated by the atomic charges are stronger than dispersive interactions and can facilitate the H₂/host binding, which can potentially lead to the increase of the hydrogen adsorption. We present results of simulations of the hydrogen adsorption for a number of model and real structures. We analyze the rotational and spatial probability distributions of the adsorbed hydrogen both with slow and fast varying atomic charge fluctuations.