ELPH SELFEN MU: Difference between revisions

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   Fermi energy:        3.5314189274 eV (dense k-point grid)
   Fermi energy:        3.5314189274 eV (dense k-point grid)


In this example, {{TAGO|ELPH_SELFEN_MU|0.1}} means that the chemical potential will be set to 3.5314189274+0.1 eV.
In this example, {{TAG|ELPH_SELFEN_MU|0.1}} means that the chemical potential will be set to (3.5314189274 + 0.1) eV.
This can be verified <tt>Chemical potential calculation</tt> section of the {{FILE|OUTCAR}} file.
This can be verified <tt>Chemical potential calculation</tt> section of the {{FILE|OUTCAR}} file.


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* [[Transport coefficients including electron-phonon scattering|Transport calculations]]
* [[Transport coefficients including electron-phonon scattering|Transport calculations]]
* [[Electron-phonon accumulators]]
* [[Electron-phonon accumulators]]
* [[Chemical potential in electron-phonon interactions]]
* {{TAG|ELPH_RUN}}
* {{TAG|ELPH_RUN}}
* {{TAG|ELPH_SELFEN_CARRIER_DEN}}
* {{TAG|ELPH_SELFEN_CARRIER_DEN}}

Latest revision as of 08:08, 24 October 2025

ELPH_SELFEN_MU = [real array]
Default: ELPH_SELFEN_MU = 0.0 

Description: List of chemical potentials at which to compute the phonon-mediated electron self-energy and transport coefficients.

Mind: Available as of VASP 6.5.0

Each chemical potential specified in the list will be added to the Fermi energy determined for the k point grid KPOINTS_ELPH. This Fermi energy might be different from the one determined in the self-consistent calculation if the k point meshes or ELPH_ISMEAR is different from ISMEAR. The Fermi energy from the self-consistent and non-self-consistent calculations can be read from the OUTCAR file. For example

$ grep "Fermi energy" OUTCAR
 Fermi energy:         3.5134142202
 Fermi energy:         3.5314189274 eV (dense k-point grid)

In this example, ELPH_SELFEN_MU = 0.1 means that the chemical potential will be set to (3.5314189274 + 0.1) eV. This can be verified Chemical potential calculation section of the OUTCAR file.

                  Number of electrons per cell
                  ----------------------------
T=      0.00000000    18.00000452
T=    100.00000000    18.00000536
T=    200.00000000    18.00000792
T=    300.00000000    18.00001223
T=    400.00000000    18.00001792
T=    500.00000000    18.00002315

                  ----------------------------
                      Chemical potential
                  ----------------------------
T=      0.00000000     3.63141893
T=    100.00000000     3.63141893
T=    200.00000000     3.63141893
T=    300.00000000     3.63141893
T=    400.00000000     3.63141893
T=    500.00000000     3.63141893
                  ----------------------------

For each of these chemical potentials and temperatures, the number of electrons per cell is computed and reported. These, in turn, can be converted to a carrier density by dividing by the volume of the unit cell. If more than one value is present in ELPH_SELFEN_MU, more columns are added to the list of chemical potentials above and more instances of the electron self-energy accumulators are created. Alternatively, you can specify a range of chemical potentials using ELPH_SELFEN_MU_RANGE. The number of rows is set by the list of temperatures in ELPH_SELFEN_TEMPS.

Alternatively, one can specify the carrier density in units of [math]\displaystyle{ {m^{-3}} }[/math] by using the ELPH_SELFEN_CARRIER_DEN tag.

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