Electron-phonon interactions from Monte-Carlo sampling - Revision history

Karsai: /* Related tags and articles */

2026-01-26T12:42:38Z

Karsai: /* ZG configuration (one-shot sampling) */

2026-01-26T12:42:26Z

ZG configuration (one-shot sampling)

← Older revision		Revision as of 12:42, 26 January 2026
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	To select the ZG configuration {{TAG\|PHON_NSTRUCT}}=0 has to be set in the {{TAG\|INCAR}} file.		To select the ZG configuration {{TAG\|PHON_NSTRUCT}}=0 has to be set in the {{TAG\|INCAR}} file.

	The ~~number of different temperatures and the~~ list of temperatures (in K) ~~have~~ to be provided using the ~~tags {{TAG\|PHON_NTLIST}} and~~ {{TAG\|PHON_TLIST}}, respectively, in the {{TAG\|INCAR}} file. An example would look like:		The list of temperatures (in K) has to be provided using the tag {{TAG\|PHON_TLIST}}, respectively, in the {{TAG\|INCAR}} file. An example would look like:
	~~{{TAGBL\|PHON_NTLIST}} = 4~~
	{{TAGBL\|PHON_TLIST}} = 0.0 100.0 200.0 350.0		{{TAGBL\|PHON_TLIST}} = 0.0 100.0 200.0 350.0
	This makes the simultaneous calculation of the ZG configuration at several temperatures possible.		This makes the simultaneous calculation of the ZG configuration at several temperatures possible.
Line 39:		Line 38:
	{{TAGBL\|ISMEAR}} = 0; {{TAGBL\|SIGMA}} = 0.1;		{{TAGBL\|ISMEAR}} = 0; {{TAGBL\|SIGMA}} = 0.1;
	{{TAGBL\|IBRION}} = 6		{{TAGBL\|IBRION}} = 6
	~~{{TAGBL\|PHON_NTLIST}} = 8~~
	{{TAGBL\|PHON_TLIST}} = 0.0 100.0 200.0 300.0 400.0 500.0 600.0 700.0		{{TAGBL\|PHON_TLIST}} = 0.0 100.0 200.0 300.0 400.0 500.0 600.0 700.0
	{{TAGBL\|PHON_NSTRUCT}} = 0		{{TAGBL\|PHON_NSTRUCT}} = 0

Csheldon at 08:14, 24 October 2025

2025-10-24T08:14:00Z

← Older revision		Revision as of 08:14, 24 October 2025
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	{{NB\|mind\|This feature is only available from VASP 6.0 or higher.}}		{{NB\|mind\|This feature is only available from VASP 6.0 or higher.}}

	For the theory on electron-phonon interactions from Monte-Carlo (MC) sampling see the [[Electron-~~phonon interactions theory~~\|theory page]].		For the theory on electron-phonon interactions from Monte-Carlo (MC) sampling, see the [[Electron-phonon_interactions_theory#Electron-phonon_interactions_from_statistical_sampling\|theory page]].

	First of all this method needs a sufficiently large supercell.		First of all this method needs a sufficiently large supercell.

Csheldon: /* Related tags and articles */

2025-10-24T08:13:18Z

Csheldon at 08:31, 20 October 2025

2025-10-20T08:31:13Z

← Older revision		Revision as of 08:31, 20 October 2025
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	{{NB\|mind\|This feature is only available from VASP 6.0 or higher.}}		{{NB\|mind\|This feature is only available from VASP 6.0 or higher.}}

	For the theory on electron-phonon interactions from Monte-Carlo (MC) sampling ~~please click~~ [[Electron-phonon interactions theory\|~~here~~]].		For the theory on electron-phonon interactions from Monte-Carlo (MC) sampling see the [[Electron-phonon interactions theory\|theory page]].

	First of all this method needs a sufficiently large supercell.		First of all this method needs a sufficiently large supercell.

Karsai: /* Full MC sampling */

2025-06-05T11:35:55Z

Full MC sampling

← Older revision		Revision as of 11:35, 5 June 2025
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	The tag {{TAG\|TEBEG}}=0 is also needed to choose the temperature at which the sampling is run.		The tag {{TAG\|TEBEG}}=0 is also needed to choose the temperature at which the sampling is run.

	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:		A sample {{TAG\|INCAR}} file for 0 K looks like the following:

Karsai: /* ZG configuration (one-shot sampling) */

2025-06-05T11:35:21Z

ZG configuration (one-shot sampling)

← Older revision		Revision as of 11:35, 5 June 2025
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	== ZG configuration (one-shot sampling) ==		== ZG configuration (one-shot sampling) ==

	M. Zacharias and F. Giustino{{cite\|zacharias:prb:2016}} introduced a one-shot method (named ZG configuration after the authors). This method is an approximation to full MC sampling. It only uses a single distorted structure and hence it is computationally much cheaper than the full MC sampling. It retains an accuracy very close to the full MC sampling for converged ~~super cell~~ sizes. For example we showed that for the zero-point renormalization of the band gap the accuracy is within 5 meV between the ZG configurations and the full MC sampling{{cite\|karsai:njp:2018}}. Hence we suggest ~~to use~~ this method preferably, ~~where~~ convergence of the ~~super cell~~ size is hard to achieve or the 5 meV accuracy is enough.		M. Zacharias and F. Giustino{{cite\|zacharias:prb:2016}} introduced a one-shot method (named ZG configuration after the authors). This method is an approximation to full MC sampling. It only uses a single distorted structure and hence it is computationally much cheaper than the full MC sampling. It retains an accuracy very close to the full MC sampling for converged supercell sizes. For example, we showed that for the zero-point renormalization of the band gap, the accuracy is within 5 meV between the ZG configurations and the full MC sampling{{cite\|karsai:njp:2018}}. Hence we suggest using this method preferably, when convergence of the supercell size is hard to achieve or the 5 meV accuracy is enough.

	To select the ZG configuration {{TAG\|PHON_NSTRUCT}}=0 has to be set in the {{TAG\|INCAR}} file.		To select the ZG configuration {{TAG\|PHON_NSTRUCT}}=0 has to be set in the {{TAG\|INCAR}} file.

Karsai: /* ZG configuration (one-shot sampling) */

2025-06-05T11:33:49Z

ZG configuration (one-shot sampling)

← Older revision		Revision as of 11:33, 5 June 2025
Line 25:		Line 25:
	== ZG configuration (one-shot sampling) ==		== ZG configuration (one-shot sampling) ==

	M. Zacharias and F. Giustino{{cite\|zacharias:prb:2016}} introduced a one-shot method (named ZG configuration after the authors). This method is an approximation to full MC sampling. It only uses a single distorted structure and hence it is ~~orders of magnitude faster~~ than the full MC sampling. It retains an accuracy very close to the full MC sampling for converged super cell sizes. For example we showed that for the zero-point renormalization of the band gap the accuracy is within 5 meV between the ZG configurations and the full MC sampling{{cite\|karsai:njp:2018}}. Hence we suggest to use this method preferably, where convergence of the super cell size is hard to achieve or the 5 meV accuracy is enough.		M. Zacharias and F. Giustino{{cite\|zacharias:prb:2016}} introduced a one-shot method (named ZG configuration after the authors). This method is an approximation to full MC sampling. It only uses a single distorted structure and hence it is computationally much cheaper than the full MC sampling. It retains an accuracy very close to the full MC sampling for converged super cell sizes. For example we showed that for the zero-point renormalization of the band gap the accuracy is within 5 meV between the ZG configurations and the full MC sampling{{cite\|karsai:njp:2018}}. Hence we suggest to use this method preferably, where convergence of the super cell size is hard to achieve or the 5 meV accuracy is enough.

	To select the ZG configuration {{TAG\|PHON_NSTRUCT}}=0 has to be set in the {{TAG\|INCAR}} file.		To select the ZG configuration {{TAG\|PHON_NSTRUCT}}=0 has to be set in the {{TAG\|INCAR}} file.

Karsai: /* Step-by-step instructions */

2025-06-05T11:32:29Z

Step-by-step instructions

← Older revision		Revision as of 11:32, 5 June 2025
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	where NUMBER runs from 1 to {{TAG\|PHON_NSTRUCT}}.		where NUMBER runs from 1 to {{TAG\|PHON_NSTRUCT}}.

	'''Step 2''': Run calculation for the previously created {{TAG\|POSCAR}} files on the desired observable. These calculations can be anything that is suitable for a MC sum <math>\langle O(T)\rangle = \frac{1}{n} \sum\limits_{i=1}^{n} O(x_{T}^{\textrm{MC,i}})</math>, for example band gap calculations, absorption spectra calculations, etc.		'''Step 2''': Run calculation for the previously created {{TAG\|POSCAR}} files on the desired observable. These calculations can be anything that is suitable for an MC sum <math>\langle O(T)\rangle = \frac{1}{n} \sum\limits_{i=1}^{n} O(x_{T}^{\textrm{MC,i}})</math>, for example, band gap calculations, absorption spectra calculations, etc.

	'''Step 3 (optional)''': Calculate the desired observable for the original "pristine" supercell. This step can be necessary when changes to an observable due to electron-phonon interactions are required. An example of such a calculation is the calculation of the band-gap renormalization due to electron-phonon interactions.		'''Step 3 (optional)''': Calculate the desired observable for the original "pristine" supercell. This step can be necessary when changes to an observable due to electron-phonon interactions are required. An example of such a calculation is the calculation of the band-gap renormalization due to electron-phonon interactions.

Karsai at 11:31, 5 June 2025

2025-06-05T11:31:48Z

← Older revision		Revision as of 11:31, 5 June 2025
Line 1:		Line 1:
	{{NB\|mind\|This feature is only available from VASP 6.0 or higher.}}		{{NB\|mind\|This feature is only available from VASP 6.0 or higher.}}

	For the theory on electron-interactions from Monte-Carlo (MC) sampling please click [[Electron-phonon interactions theory\|here]].		For the theory on electron-phonon interactions from Monte-Carlo (MC) sampling please click [[Electron-phonon interactions theory\|here]].

	First of all this method needs a sufficiently large ~~super cell~~.		First of all this method needs a sufficiently large supercell.
	It also involves phonon calculations for the <math>\Gamma</math> point (see {{TAG\|Phonons from finite differences}}). So many tags in the {{TAG\|INCAR}} will be used from the phonon calculations.		It also involves phonon calculations for the <math>\Gamma</math> point (see {{TAG\|Phonons from finite differences}}). So many tags in the {{TAG\|INCAR}} will be used from the phonon calculations.

← Older revision		Revision as of 12:42, 26 January 2026
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	* {{TAG\|PHON_LMC}}		* {{TAG\|PHON_LMC}}
	* {{TAG\|PHON_NSTRUCT}}		* {{TAG\|PHON_NSTRUCT}}
	* {{TAG\|PHON_NTLIST}}
	* {{TAG\|PHON_TLIST}}		* {{TAG\|PHON_TLIST}}
	* [[Electron-phonon_interactions_theory#Electron-phonon_interactions_from_statistical_sampling \| Electron-phonon interactions from statistical sampling]]		* [[Electron-phonon_interactions_theory#Electron-phonon_interactions_from_statistical_sampling \| Electron-phonon interactions from statistical sampling]]

← Older revision		Revision as of 12:42, 26 January 2026
Line 29:		Line 29:
	To select the ZG configuration {{TAG\|PHON_NSTRUCT}}=0 has to be set in the {{TAG\|INCAR}} file.		To select the ZG configuration {{TAG\|PHON_NSTRUCT}}=0 has to be set in the {{TAG\|INCAR}} file.

	The ~~number of different temperatures and the~~ list of temperatures (in K) ~~have~~ to be provided using the ~~tags {{TAG\|PHON_NTLIST}} and~~ {{TAG\|PHON_TLIST}}, respectively, in the {{TAG\|INCAR}} file. An example would look like:		The list of temperatures (in K) has to be provided using the tag {{TAG\|PHON_TLIST}}, respectively, in the {{TAG\|INCAR}} file. An example would look like:
	~~{{TAGBL\|PHON_NTLIST}} = 4~~
	{{TAGBL\|PHON_TLIST}} = 0.0 100.0 200.0 350.0		{{TAGBL\|PHON_TLIST}} = 0.0 100.0 200.0 350.0
	This makes the simultaneous calculation of the ZG configuration at several temperatures possible.		This makes the simultaneous calculation of the ZG configuration at several temperatures possible.
Line 39:		Line 38:
	{{TAGBL\|ISMEAR}} = 0; {{TAGBL\|SIGMA}} = 0.1;		{{TAGBL\|ISMEAR}} = 0; {{TAGBL\|SIGMA}} = 0.1;
	{{TAGBL\|IBRION}} = 6		{{TAGBL\|IBRION}} = 6
	~~{{TAGBL\|PHON_NTLIST}} = 8~~
	{{TAGBL\|PHON_TLIST}} = 0.0 100.0 200.0 300.0 400.0 500.0 600.0 700.0		{{TAGBL\|PHON_TLIST}} = 0.0 100.0 200.0 300.0 400.0 500.0 600.0 700.0
	{{TAGBL\|PHON_NSTRUCT}} = 0		{{TAGBL\|PHON_NSTRUCT}} = 0

← Older revision		Revision as of 08:13, 24 October 2025
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	* {{TAG\|PHON_NTLIST}}		* {{TAG\|PHON_NTLIST}}
	* {{TAG\|PHON_TLIST}}		* {{TAG\|PHON_TLIST}}
			* [[Electron-phonon_interactions_theory#Electron-phonon_interactions_from_statistical_sampling \| Electron-phonon interactions from statistical sampling]]
	* [[Bandgap renormalization due to electron-phonon coupling\|Band-structure renormalization]]		* [[Bandgap renormalization due to electron-phonon coupling\|Band-structure renormalization]]
	* [[Transport coefficients including electron-phonon scattering\|Transport calculations]]		* [[Transport coefficients including electron-phonon scattering\|Transport calculations]]

← Older revision		Revision as of 11:35, 5 June 2025
Line 50:		Line 50:
	The tag {{TAG\|TEBEG}}=0 is also needed to choose the temperature at which the sampling is run.		The tag {{TAG\|TEBEG}}=0 is also needed to choose the temperature at which the sampling is run.

	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:		A sample {{TAG\|INCAR}} file for 0 K looks like the following: