| name | incar-smearing-precision |
| description | Choose and validate VASP smearing, precision, and static/relax accuracy tags such as ISMEAR, SIGMA, EDIFF, PREC, LREAL, LASPH, ADDGRID, and related output precision settings. Use when preparing INCAR for metals, semiconductors, insulators, surfaces, DOS/band calculations, or energy comparisons. |
INCAR Smearing and Precision
Use this skill as an INCAR modifier whenever occupation and precision choices affect accuracy or convergence.
INCAR Contract
Adds or Sets
ISMEAR and SIGMA based on material class and workflow stage.
EDIFF, PREC, LREAL, LASPH, and related accuracy tags when the workflow template is incomplete.
- Static/DOS/band choices that differ from relaxation choices, documented in notes.
Defaults
- Unknown semiconductor/insulator: conservative Gaussian smearing, typically
ISMEAR = 0, small SIGMA.
- Metal relaxation or metallic surface: metallic smearing may be appropriate, but keep the choice consistent across energy differences.
- DOS and band-structure post-SCF steps require careful occupation settings and should not silently inherit a rough relaxation INCAR.
Forbids
- Do not use a large metallic
SIGMA for final bandgap extraction unless the workflow explicitly uses it as a controlled approximation.
- Do not compare energies across directories with different smearing settings unless that difference is the study variable.
- Do not lower precision tags just to speed up a production calculation; route performance-only requests through
incar-performance.
Handoff
After applying this modifier, call incar-validator before run-vasp if the calculation will be submitted.