Predicting 2D silicon allotropes on SnS2

Dispersion interactions in silicon allotropes.

van der Waals interactions are known to play a key role in the formation of weakly bound solids, such as molecular or layered crystals. Here we show that the correct quantum-chemical description of van der Waals dispersion is also essential for a correct description of the relative stability between purely covalently-bound solids like silicon allotropes. To this end, we apply periodic local MP2...

Low-density silicon allotropes for photovoltaic applications

Maximilian Amsler,1 Silvana Botti,2 Miguel A. L. Marques,3 Thomas J. Lenosky,4 and Stefan Goedecker1,* 1Department of Physics, Universität Basel, Klingelbergstr. 82, 4056 Basel, Switzerland 2Institut für Festkörpertheorie und -optik, Friedrich-Schiller-Universität Jena and European Theoretical Spectroscopy Facility, Max-Wien-Platz 1, 07743 Jena, Germany 3Institut für Physik, Martin-Luther-Unive...

sp3-Bonded silicon allotropes based on the Kelvin problem.

The Kelvin problem, how to partition three-dimensional space into cells of equal volume with minimal area, is a fascinating one. Aggregations of bubbles are naturally physical illustrations of the Kelvin problem. And the superconductor Na8Si46 as an inspiration leads to an amazing discovery of the Weaire-Phelan (WP) structure of foam - the optimal solution to the Kelvin problem to date. Here ba...

Predicting experimentally stable allotropes: Instability of penta-graphene.

In recent years, a plethora of theoretical carbon allotropes have been proposed, none of which has been experimentally isolated. We discuss here criteria that should be met for a new phase to be potentially experimentally viable. We take as examples Haeckelites, 2D networks of sp(2)-carbon-containing pentagons and heptagons, and "penta-graphene," consisting of a layer of pentagons constructed f...

NITech - LFG joint workshop on carbon allotropes