Electron-phonon interactions from Monte-Carlo sampling: Difference between revisions
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Additionally the {{TAG|PHON_LBOSE}} can be set ''.TRUE.'' or ''.FALSE.'' (default {{TAG|PHON_LBOSE}}=''.TRUE.''), which selects Bose-Einstein or Maxwell-Boltzmann statistics, respectively. | Additionally the {{TAG|PHON_LBOSE}} can be set ''.TRUE.'' or ''.FALSE.'' (default {{TAG|PHON_LBOSE}}=''.TRUE.''), which selects Bose-Einstein or Maxwell-Boltzmann statistics, respectively. | ||
A sample {{TAG|INCAR}} file for 0 K looks like the following: | |||
System = DEFAULT | |||
PREC = Accurate | |||
ISMEAR = 0; SIGMA = 0.1; | |||
IBRION = 6 | |||
PHON_LMC = .TRUE. | |||
PHON_NSTRUCT = 100 | |||
TEBE = 0.0 | |||
Revision as of 10:04, 9 April 2019
Important: This feature will be only available from VASP6.0 or higher.
First of all this method needs a sufficiently large super cell. It also involves phonon calculations for the [math]\displaystyle{ \Gamma }[/math] point (see Phonons from finite differences). So many tags in the INCAR will be used from the phonon calculations.
To enable electron-phonon interactions from MC methods PHON_LMC=.TRUE. has to be set in the INCAR file.
Full MC sampling
The tag PHON_NSTRUCT sets the number of structures generated due to the MC sampling. Convergence of the observable with respect to this number should be monitored.
The tag TEBEG=0 is also needed to choose the temperature at which the sampling is run.
Additionally the PHON_LBOSE can be set .TRUE. or .FALSE. (default PHON_LBOSE=.TRUE.), which selects Bose-Einstein or Maxwell-Boltzmann statistics, respectively.
A sample INCAR file for 0 K looks like the following:
System = DEFAULT PREC = Accurate ISMEAR = 0; SIGMA = 0.1; IBRION = 6 PHON_LMC = .TRUE. PHON_NSTRUCT = 100 TEBE = 0.0
== ZG configuration (one-shot sampling)
A sample INCAR file for the