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ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full... more
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
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ABSTRACT The dispersion interaction between a pair of parallel DNA double-helix structures is investigated by means of the van der Waals density functional (vdW-DF) method. Each double-helix structure consists of an infinite repetition of... more
ABSTRACT The dispersion interaction between a pair of parallel DNA double-helix structures is investigated by means of the van der Waals density functional (vdW-DF) method. Each double-helix structure consists of an infinite repetition of one B-DNA coil with 10 base pairs. This parameter-free density functional theory (DFT) study illustrates the initial step in a proposed vdW-DF computational strategy for large biomolecular problems. The strategy is to first perform a survey of interaction geometries, based on the evaluation of the van der Waals (vdW) attraction, and then limit the evaluation of the remaining DFT parts (specifically the expensive study of the kinetic-energy repulsion) to the thus identified interesting geometries. Possibilities for accelerating this second step is detailed in a separate study. For the B-DNA dimer, the variation in van der Waals attraction is explored at relatively short distances (although beyond the region of density overlap) for a 360 degrees rotation. This study highlights the role of the structural motifs, like the grooves, in enhancing or reducing the vdW interaction strength. We find that to a first approximation, it is possible to compare the DNA double strand at large wall-to-wall separations to the cylindrical shape of a carbon nanotube (which is almost isotropic under rotation). We compare our first-principles results with the atom-based dispersive interaction predicted by DFT-D2 [J. Comp. Chem. 27, 1787 (2006)] and find agreement in the asymptotic region. However, we also find that the differences in the enhancement that occur at shorter distances reveal characteristic features that result from the fact that the vdW-DF method is an electron-based (as opposed to atom-based) description.
The existence of one-dimensional (1D) electronic states in Cu/Cu(111) chains assembled by atomic manipulation is revealed by low-temperature scanning tunneling spectroscopy and density functional theory (DFT) calculations. Our... more
The existence of one-dimensional (1D) electronic states in Cu/Cu(111) chains assembled by atomic manipulation is revealed by low-temperature scanning tunneling spectroscopy and density functional theory (DFT) calculations. Our experimental analysis of the chain-localized electron dynamics shows that the dispersion is fully described within a 1D tight-binding approach. DFT calculations confirm the confinement of unoccupied states to the chain in the relevant energy range, along with a significant extension of these states into the vacuum region.
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... Science, 297 (2002), p. 1853. [5] TM Wallis, N Nilius and W Ho. Phys. Rev. Lett., 89 (2002), p. 236802. [6] J Repp, G Meyer, KH Rieder and P Hyldgaard. Phys. Rev. Lett., 91 (2003), p. 206102. [7] N Nilius, TM Wallis and W Ho. Phys.... more
... Science, 297 (2002), p. 1853. [5] TM Wallis, N Nilius and W Ho. Phys. Rev. Lett., 89 (2002), p. 236802. [6] J Repp, G Meyer, KH Rieder and P Hyldgaard. Phys. Rev. Lett., 91 (2003), p. 206102. [7] N Nilius, TM Wallis and W Ho. Phys. Rev. Lett., 90 (2003), p. 46808. ...
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Research Interests: Condensed Matter Physics, Quantum Physics, Biomedical Engineering, Surface Science, Morphology, and 15 moreCarbon Nanotubes, Carbon Nanotube, Ab initio calculations, Fullerenes, Integer quantum hall effect, van der Waals interaction, Surface topography, van der Waals interactions, Van Der Waals, Electron Density, Surface Structure, Roughness, Kinetic Energy, Nanostructured Material, and Quantum Effects
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An early van der Waals density functional (vdW-DF) described layered systems (such as graphite and graphene dimers) using a layer-averaged electron density in the evaluation of nonlocal correlations. This early vdW-DF version was also... more
An early van der Waals density functional (vdW-DF) described layered systems (such as graphite and graphene dimers) using a layer-averaged electron density in the evaluation of nonlocal correlations. This early vdW-DF version was also adapted to approximate the ...
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... (http://iopscience.iop.org/0295-5075/59/2/265) Download details: IP Address: 66.249.71.201 The article was downloaded on 16/06/2011 at 05:55 Please note that terms and conditions apply. ... Page 4. P. Hyldgaard et al.:... more
... (http://iopscience.iop.org/0295-5075/59/2/265) Download details: IP Address: 66.249.71.201 The article was downloaded on 16/06/2011 at 05:55 Please note that terms and conditions apply. ... Page 4. P. Hyldgaard et al.: Surface-state–mediated three-adsorbate interaction 267 ...