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