Orbital Dependent Exchange-Only Methods for Periodic Systems

P. S"ule; S. Kurth; V. Van Doren

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arXiv · cond-mat/9907274

Orbital Dependent Exchange-Only Methods for Periodic Systems

P. S"ule·S. Kurth·V. Van Doren

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Abstract

Various orbital-dependent exchange-only potentials are studied which exhibit correct long-range asymptotic behaviour. We present the first application of these potentials for polymers and by one of these potentials for molecules. Kohn-Sham type calculations have been carried out for polyethylene in order to make valuable comparison of these potentials with each other as well as with Hartree-Fock and exchange-only LDA methods. The Kohn-Sham band gap obtained with the optimized effective potetial method is corrected with the exchange contribution to the derivative discontinuity of the exchange-correlation potential. The corrected band gap obtained with the Slater's exchange potential is 9.7 eV close to the experiment.

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P. S"ule, S. Kurth, V. Van Doren. 1999-07-19. Orbital Dependent Exchange-Only Methods for Periodic Systems. https://arxiv.org/abs/cond-mat/9907274

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