AB-INITIO SIMULATIONS IN MATERIALS SCIENCE - VASP
AB-INITIO SIMULATIONS IN MATERIALS SCIENCE - VASP
AB-INITIO SIMULATIONS IN MATERIALS SCIENCE - VASP
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Hartree-Fock methods II<br />
Hartree-Fock equations<br />
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e 2 ∑<br />
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Problems with Hartree-Fock calculations<br />
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(10)<br />
Computational effort scales badly with the number of electrons<br />
Neglect of correlations<br />
- Too wide band gaps, too small band widths<br />
- Exchange-operator for metallic systems singular at the Fermi level<br />
J. HAFNER, <strong>AB</strong>-<strong><strong>IN</strong>ITIO</strong> <strong>MATERIALS</strong> <strong>SIMULATIONS</strong> Page 10
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