ELPH_ISMEAR

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ELPH_ISMEAR = -15 | -14 | -5 | -4 | -1 | 0 | [integer]>0
Default: ELPH_ISMEAR = 0 

Description: Chooses the smearing method to determine the fermi level and chemical potential before an electron-phonon calculation.


ELPH_ISMEAR is very similar to ISMEAR. The difference is that ELPH_ISMEAR is used to determine the chemical potential in the context of electron-phonon calculation. The Kohn-Sham states for which to calculate the chemical potential correspond to the k-point grid specified via the KPOINTS_ELPH file.

The chemical potential is determined for the list of temperatures ELPH_SELFEN_TEMPS and carrier concentrations specified by ELPH_SELFEN_CARRIER_DEN or ELPH_SELFEN_CARRIER_PER_CELL. Alternatively, one can specify the chemical potential and determine the carrier concentration using ELPH_SELFEN_MU.

Tag options

ELPH_ISMEAR > 1
Method of Methfessel-Paxton of order ELPH_ISMEAR (for details see ISMEAR)
ELPH_ISMEAR = 0
Gaussian smearing (for details see ISMEAR)
ELPH_ISMEAR = -1
Fermi-Dirac smearing (for details see ISMEAR)
ELPH_ISMEAR = -4
Tetrahedron method (zero temperature) (for details see ISMEAR)
ELPH_ISMEAR = -5
Tetrahedron method (zero temperature) with Blöchl corrections (for details see ISMEAR)
ELPH_ISMEAR = -14
Tetrahedron method (finite temperature)
ELPH_ISMEAR = -15
Tetrahedron method (finite temperature) with Blöchl corrections

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