Structure and binding in crystals of cagelike molecules: Hexamine and platonic hydrocarbons
Artikel i vetenskaplig tidskrift, 2010
In this paper, we show that first-principle calculations using a van der Waals density functional (vdW-DF) [M. Dion, H. Rydberg, E. Schroumlder, D. C. Langreth, and B. I. Lundqvist, Phys. Rev. Lett. 92, 246401 (2004)] permit the determination of molecular crystal structure within density functional theory (DFT). We study the crystal structures of hexamine and the platonic hydrocarbons (cubane and dodecahedrane). The calculated lattice parameters and cohesion energy agree well with experiments. Further, we examine the asymptotic accounts of the van der Waals forces by comparing full vdW-DF with asymptotic atom-based pair potentials extracted from vdW-DF. The character of the binding differs in the two cases, with vdW-DF giving a significant enhancement at intermediate and relevant binding separations. We analyze consequences of this result for methods such as DFT-D and question DFT-D's transferability over the full range of separations.
density functional theory
binding energy
ab initio calculations
DER-WAALS INTERACTIONS
VAN
DENSITY-FUNCTIONAL THEORY
structure
COMPLEXES
van der Waals forces
DFT-D
SOLID CUBANE
crystal binding
crystal
ENERGY
FORCE-FIELD
organic
compounds
lattice constants
GENERALIZED GRADIENT APPROXIMATION
X-RAY
Författare
Kristian Berland
Chalmers, Teknisk fysik, Elektronikmaterial
Per Hyldgaard
Chalmers, Teknisk fysik, Elektronikmaterial
Journal of Chemical Physics
0021-9606 (ISSN) 1089-7690 (eISSN)
Vol. 132 13 (Published: April 7 2010) (Article Number: 134705)- 134705Styrkeområden
Nanovetenskap och nanoteknik
Livsvetenskaper och teknik (2010-2018)
Materialvetenskap
Ämneskategorier
Den kondenserade materiens fysik
DOI
10.1063/1.3366652