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arXiv · 0710.0718

Exchange-energy functionals for finite two-dimensional systems

S. Pittalis·E. Rasanen·N. Helbig·E. K. U. Gross
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Abstract

Implicit and explicit density functionals for the exchange energy in finite two-dimensional systems are developed following the approach of Becke and Roussel [Phys. Rev. A 39, 3761 (1989)]. Excellent agreement for the exchange-hole potentials and exchange energies is found when compared with the exact-exchange reference data for the two-dimensional uniform electron gas and few-electron quantum dots, respectively. Thereby, this work significantly improves the availability of approximate density functionals for dealing with electrons in quasi-two-dimensional structures, which have various applications in semiconductor nanotechnology.

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S. Pittalis, E. Rasanen, N. Helbig, E. K. U. Gross. 2007-12-14. Exchange-energy functionals for finite two-dimensional systems. https://doi.org/10.1103/physrevb.76.235314

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