6533b856fe1ef96bd12b288f
RESEARCH PRODUCT
Density gradients for the exchange energy of electrons in two dimensions
J. G. VilhenaStefano PittalisMiguel A. L. MarquesEsa RäsänenEsa Räsänensubject
PhysicsStrongly Correlated Electrons (cond-mat.str-el)Orbital-free density functional theoryExchange interactionFOS: Physical sciences02 engineering and technology021001 nanoscience & nanotechnology01 natural sciencesAtomic and Molecular Physics and OpticsHybrid functionalCondensed Matter - Strongly Correlated ElectronsQuantum dotQuantum mechanics0103 physical sciencesDensity functional theoryLocal-density approximation010306 general physics0210 nano-technologyQuantumElectronic densitydescription
We derive a generalized gradient approximation to the exchange energy to be used in density functional theory calculations of two-dimensional systems. This class of approximations has a long and successful history, but it has not yet been fully investigated for electrons in two dimensions. We follow the approach originally proposed by Becke for three-dimensional systems [Int. J. Quantum Chem. 23, 1915 (1983), J. Chem. Phys. 85, 7184 (1986)]. The resulting functional depends on two parameters that are adjusted to a test set of parabolically confined quantum dots. Our exchange functional is then tested on a variety of systems with promising results, reducing the error in the exchange energy by a factor of 4 with respect to the simple local density approximation.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2009-01-07 |