ISTART: Difference between revisions
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:These values might differ from the old values, that are stored in the {{FILE|WAVECAR}} file. | :These values might differ from the old values, that are stored in the {{FILE|WAVECAR}} file. | ||
:If the {{FILE|WAVECAR}} file is missing or if the {{FILE|WAVECAR}} file contains an inappropriate number of bands and/or k-points the flag {{TAG|ISTART}} will be set to 0 (see above). | :If the {{FILE|WAVECAR}} file is missing or if the {{FILE|WAVECAR}} file contains an inappropriate number of bands and/or k-points the flag {{TAG|ISTART}} will be set to 0 (see above). | ||
:The usage of {{TAG|ISTART}}=1 is recommended if the size/shape of the supercell (see section \ref{pullay}) or the cut-off energy changed with respect to the last run and if one wishes to redefine the set of plane waves according to a new setting. | |||
:{{TAG|ISTART}}=1 is the usual setting for convergence tests with respect to the cut-off energy and for all jobs where the volume/cell-shape varies (e.g. to calculate binding energy curves looping over a set of volumes). | |||
*{{TAG|ISTART}}=2 | *{{TAG|ISTART}}=2 | ||
*{{TAG|ISTART}}=3 | *{{TAG|ISTART}}=3 | ||
---- | ---- | ||
Revision as of 16:17, 28 January 2011
ISTART = 0 | 1 | 2 | 3
| Default: ISTART | = 1 | if WAVECAR exists |
| = 0 | else |
Description: ISTART determines whether or not to read the WAVECAR file.
- ISTART=0
- Start job: "begin from scratch". Initialize the orbitals according to the flag INIWAV.
- ISTART=1
- Continuation job: "restart with constant energy cut-off". Orbitals are read from the WAVECAR file (usage is restricted in the parallel version).
- The set of plane waves will be redefined and re-padded according to the new cell size/shape (POSCAR) and the new plane wave cut-off (INCAR).
- These values might differ from the old values, that are stored in the WAVECAR file.
- If the WAVECAR file is missing or if the WAVECAR file contains an inappropriate number of bands and/or k-points the flag ISTART will be set to 0 (see above).
- The usage of ISTART=1 is recommended if the size/shape of the supercell (see section \ref{pullay}) or the cut-off energy changed with respect to the last run and if one wishes to redefine the set of plane waves according to a new setting.
- ISTART=1 is the usual setting for convergence tests with respect to the cut-off energy and for all jobs where the volume/cell-shape varies (e.g. to calculate binding energy curves looping over a set of volumes).
- ISTART=2
- ISTART=3