Be careful with the default smearing method (ISMEAR=1): Difference between revisions
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The default for {{TAG|ISMEAR}} is 2 in | The default for {{TAG|ISMEAR}} is 1 in VASP. This setting is not appropriate for | ||
insulators and semiconductors, and can results in one-electron occupancies that | |||
are larger than 1 (2 for non spinpolarized) systems, and conversely | |||
some states being occupied by less than 1 electron close to the Fermi-level. | |||
It is strongly recommended to set {{TAG|ISMEAR}}=0 in the INCAR file | |||
and use a small width {{TAG|SIGMA}}=0.05 (do not make SIGMA too small, | |||
values below 0.001 can also lead to undesirable symmetry breaking). | |||
---- | ---- | ||
[[Category:Calculational issues]] | [[Category:Calculational issues]] | ||
Revision as of 11:28, 14 October 2020
The default for ISMEAR is 1 in VASP. This setting is not appropriate for insulators and semiconductors, and can results in one-electron occupancies that are larger than 1 (2 for non spinpolarized) systems, and conversely some states being occupied by less than 1 electron close to the Fermi-level. It is strongly recommended to set ISMEAR=0 in the INCAR file and use a small width SIGMA=0.05 (do not make SIGMA too small, values below 0.001 can also lead to undesirable symmetry breaking).