ISMEAR: Difference between revisions
No edit summary |
No edit summary |
||
Line 5: | Line 5: | ||
*{{TAG|ISMEAR}}=''N'' (''N''>0): method of Methfessel-Paxton order ''N''. | *{{TAG|ISMEAR}}=''N'' (''N''>0): method of Methfessel-Paxton order ''N''. | ||
:'''Mind''': For the Methfessel-Paxton scheme the partial occupancies can be negative. | :'''Mind''': For the Methfessel-Paxton scheme the partial occupancies can be negative. | ||
*{{TAG|ISMEAR}}=0: | *{{TAG|ISMEAR}}=0: Gaussian smearing. | ||
*{{TAG|ISMEAR}}=−1: | *{{TAG|ISMEAR}}=−1: Fermi smearing. | ||
*{{TAG|ISMEAR}}=−2: | *{{TAG|ISMEAR}}=−2:partial occupancies are read in from the {{FILE|WAVECAR}} or {{FILE|INCAR}} file, and kept fixed throughout run. | ||
:To set the occupancies specify | |||
{{TAG|FERWE}} = f1 f2 f3 ... f({{TAG|NBANDS}}) | |||
:and for spin-polarized calculations, additionally | |||
{{TAG|FERDO}} = f1 f2 f3 ... f({{TAG|NBANDS}}) | |||
:in the {{TAG|INCAR}} file. The (partial) occupancies must be specified for all bands and k-points. The band-index runs fastest. The occupancies must be between 0 and 1 (for spin-polarized and non-spin-polarized calculations). | |||
:'''Mind''': Partial occupancies are also written to the {{FILE|OUTCAR}} file, but in this case they are multiplied by 2, i.e. they are between 0 and 2. | |||
*{{TAG|ISMEAR}}=−3: | *{{TAG|ISMEAR}}=−3: | ||
*{{TAG|ISMEAR}}=−4: | *{{TAG|ISMEAR}}=−4: |
Revision as of 16:12, 23 May 2011
ISMEAR = -5 | -4 | -3 | -2 | -1 | 0 | [integer]>0
Default: ISMEAR = 1
Description: ISMEAR determines how the partial occupancies fnk are set for each orbital. SIGMA determines the width of the smearing in eV.
- ISMEAR=N (N>0): method of Methfessel-Paxton order N.
- Mind: For the Methfessel-Paxton scheme the partial occupancies can be negative.
- ISMEAR=0: Gaussian smearing.
- ISMEAR=−1: Fermi smearing.
- ISMEAR=−2:partial occupancies are read in from the WAVECAR or INCAR file, and kept fixed throughout run.
- To set the occupancies specify
FERWE = f1 f2 f3 ... f(NBANDS)
- and for spin-polarized calculations, additionally
FERDO = f1 f2 f3 ... f(NBANDS)
- in the INCAR file. The (partial) occupancies must be specified for all bands and k-points. The band-index runs fastest. The occupancies must be between 0 and 1 (for spin-polarized and non-spin-polarized calculations).
- Mind: Partial occupancies are also written to the OUTCAR file, but in this case they are multiplied by 2, i.e. they are between 0 and 2.