NVE ensemble - Revision history

Singraber at 10:38, 21 November 2023

2023-11-21T10:38:59Z

← Older revision		Revision as of 10:38, 21 November 2023
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	The [[NVE ensemble]] (micro-canonical ensemble) is a [[:Category:Ensembles\|statistical ensemble]] that is used to study material properties under the conditions of a constant particle number N, constant volume V and an internal energy E ~~fluctuating around an equilibrium value <math>\langle E \rangle </math>~~. This page describes how to sample the NVE ensemble from a [[Molecular dynamics calculations\|molecular-dynamics]] run.		The [[NVE ensemble]] (micro-canonical ensemble) is a [[:Category:Ensembles\|statistical ensemble]] that is used to study material properties under the conditions of a constant particle number N, constant volume V and a conserved internal energy E (up to numerical inaccuracies). This page describes how to sample the NVE ensemble from a [[Molecular dynamics calculations\|molecular-dynamics]] run.

	''' Instructions for setting up a NVE ensemble '''		''' Instructions for setting up a NVE ensemble '''

Huebsch: Huebsch moved page Construction:NVE ensemble to NVE ensemble without leaving a redirect

2023-04-24T11:40:01Z

Huebsch moved page Construction:NVE ensemble to NVE ensemble without leaving a redirect

← Older revision	Revision as of 11:40, 24 April 2023
(No difference)

Jona at 15:12, 11 August 2022

2022-08-11T15:12:42Z

← Older revision		Revision as of 15:12, 11 August 2022
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	The [[NVE ensemble]] (micro-canonical ensemble) is a [[:Category:Ensembles\|statistical ensemble]] that is used to study material properties under the conditions of a constant particle number N, constant volume V and an internal energy E fluctuating around an equilibrium value E. This page describes how to sample the NVE ensemble from a [[Molecular dynamics calculations\|molecular-dynamics]] run.		The [[NVE ensemble]] (micro-canonical ensemble) is a [[:Category:Ensembles\|statistical ensemble]] that is used to study material properties under the conditions of a constant particle number N, constant volume V and an internal energy E fluctuating around an equilibrium value <math>\langle E \rangle </math>. This page describes how to sample the NVE ensemble from a [[Molecular dynamics calculations\|molecular-dynamics]] run.

	''' Instructions for setting up a NVE ensemble '''		''' Instructions for setting up a NVE ensemble '''

Jona at 14:35, 10 August 2022

2022-08-10T14:35:13Z

← Older revision		Revision as of 14:35, 10 August 2022
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	{{TAGBL\|ANDERSEN_PROB}} = 0.0 # setting Andersen collision probability to zero to get NVE enseble		{{TAGBL\|ANDERSEN_PROB}} = 0.0 # setting Andersen collision probability to zero to get NVE enseble
	{{NB\|mind\| This {{FILE\|INCAR}} file only contains the parameters for the molecular-dynamics part. The [[Electronic minimization\|electronic minimization]] or the [[Machine-learned force fields\|machine learning]] tags have to be added.}}		{{NB\|mind\| This {{FILE\|INCAR}} file only contains the parameters for the molecular-dynamics part. The [[Electronic minimization\|electronic minimization]] or the [[Machine-learned force fields\|machine learning]] tags have to be added.}}


	==Related tags and articles==		==Related tags and articles==

Karsai at 11:21, 5 August 2022

2022-08-05T11:21:24Z

← Older revision		Revision as of 11:21, 5 August 2022
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	There are two choices of thermostats which can be adjusted to set up a [[Molecular dynamics calculations\|molecular-dynamics]] run.		There are two choices of thermostats which can be adjusted to set up a [[Molecular dynamics calculations\|molecular-dynamics]] run.
	The [[Andersen thermostat]] can be used by setting the collision probability ({{TAG\|ANDERSEN_PROB}}) with the fictitious heat bath to zero and the [[Nose-Hoover thermostat]] by setting the mass of the virtual degree of freedom ({{TAG\|SMASS}}) to minus three. Both settings will switch the thermostat off, such that the velocities are determined by the [[Hellmann-Feynman forces]] or [[Machine-learned force fields]] only.		The [[Andersen thermostat]] can be used by setting the collision probability ({{TAG\|ANDERSEN_PROB}}) with the fictitious heat bath to zero and the [[Nose-Hoover thermostat]] by setting the mass of the virtual degree of freedom ({{TAG\|SMASS}}) to minus three. Both settings will switch the thermostat off, such that the velocities are determined by the [[Hellmann-Feynman forces]] or [[Machine-learned force fields]] only.
	See table for the corresponding MDALGO setting and related tags.		See table for the corresponding {{TAG\|MDALGO}} setting and related tags.

	{\|class="wikitable" style="margin:aut		{\|class="wikitable" style="margin:aut

Jona at 14:46, 20 July 2022

2022-07-20T14:46:47Z

← Older revision		Revision as of 14:46, 20 July 2022
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	A general guide for molecular-dynamics simulations can be found on the [[Molecular dynamics calculations\|molecular-dynamics]] page.		A general guide for molecular-dynamics simulations can be found on the [[Molecular dynamics calculations\|molecular-dynamics]] page.

	''An example {{FILE\|INCAR}} file for the [[Andersen thermostat]] ~~could look like~~''		''An example {{FILE\|INCAR}} file for the [[Andersen thermostat]]''

	#INCAR molecular-dynamics tags NVE ensemble		#INCAR molecular-dynamics tags NVE ensemble

Jona at 14:46, 20 July 2022

2022-07-20T14:46:13Z

← Older revision		Revision as of 14:46, 20 July 2022
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	The additional tags in the column for every thermostat have to be set to the given values. Otherwise the NVE ensemble will not be realized.		The additional tags in the column for every thermostat have to be set to the given values. Otherwise the NVE ensemble will not be realized.
	There are two implementations of the [[Nose-Hoover thermostat]] in VASP which will give the same results. The {{TAG\|MDALGO}}=0 version can be used even if the code was compiled without the precompiler option [[Precompiler_options#-Dtbdyn\|-Dtbdyn]].		There are two implementations of the [[Nose-Hoover thermostat]] in VASP which will give the same results. The {{TAG\|MDALGO}}=0 version can be used even if the code was compiled without the precompiler option [[Precompiler_options#-Dtbdyn\|-Dtbdyn]]. To enforce constant volume throughout the calculation, {{TAG\|ISIF}} has to be set to less than three. The cell shape and volume have to be preoptimized when doing NVT simulations. This can either be done with a [[NpT_ensemble\|NPT]] [[Molecular dynamics calculations\|molecular-dynamics]] run or by performing structure and volume optimization with {{TAG\|IBRION}}=1 or 2 and setting {{TAG\|ISIF}}>2.
	~~Other tags related to~~ molecular-dynamics simulations can be found [[Molecular dynamics calculations\|~~here~~]].		A general guide for molecular-dynamics simulations can be found on the [[Molecular dynamics calculations\|molecular-dynamics]] page.

	''An example {{FILE\|INCAR}} file for the [[Andersen thermostat]] could look like''		''An example {{FILE\|INCAR}} file for the [[Andersen thermostat]] could look like''

Jona at 14:43, 20 July 2022

2022-07-20T14:43:44Z

← Older revision		Revision as of 14:43, 20 July 2022
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	There are two choices of thermostats which can be adjusted to set up a [[Molecular dynamics calculations\|molecular-dynamics]] run.		There are two choices of thermostats which can be adjusted to set up a [[Molecular dynamics calculations\|molecular-dynamics]] run.
	The [[Andersen thermostat]] can be used by setting the collision probability ({{TAG\|ANDERSEN_PROB}}) with the fictitious heat bath to zero and the [[Nose-Hoover thermostat]] by setting the mass of the virtual degree of freedom ({{TAG\|SMASS}}) to minus three. Both settings will switch the thermostat of such that the velocities are determined by the [[Hellmann-Feynman forces]] or [[Machine-learned force fields]] only.		The [[Andersen thermostat]] can be used by setting the collision probability ({{TAG\|ANDERSEN_PROB}}) with the fictitious heat bath to zero and the [[Nose-Hoover thermostat]] by setting the mass of the virtual degree of freedom ({{TAG\|SMASS}}) to minus three. Both settings will switch the thermostat off, such that the velocities are determined by the [[Hellmann-Feynman forces]] or [[Machine-learned force fields]] only.
	See table for the corresponding MDALGO setting and related tags.		See table for the corresponding MDALGO setting and related tags.

Jona at 14:43, 20 July 2022

2022-07-20T14:43:21Z

← Older revision		Revision as of 14:43, 20 July 2022
Line 4:		Line 4:

	There are two choices of thermostats which can be adjusted to set up a [[Molecular dynamics calculations\|molecular-dynamics]] run.		There are two choices of thermostats which can be adjusted to set up a [[Molecular dynamics calculations\|molecular-dynamics]] run.
	The [[Andersen thermostat]] can be used by setting the collision probability ({{TAG\|ANDERSEN_PROB}}) with the fictitious heat bath to zero and the [[Nose-Hoover thermostat]] by setting the mass of the virtual degree of freedom ({TAG\|SMASS}) to minus three. Both settings will switch the thermostat of such that the velocities are determined by the [[Hellmann-Feynman forces]] or [[Machine-learned force fields]] only.		The [[Andersen thermostat]] can be used by setting the collision probability ({{TAG\|ANDERSEN_PROB}}) with the fictitious heat bath to zero and the [[Nose-Hoover thermostat]] by setting the mass of the virtual degree of freedom ({{TAG\|SMASS}}) to minus three. Both settings will switch the thermostat of such that the velocities are determined by the [[Hellmann-Feynman forces]] or [[Machine-learned force fields]] only.
	See table for the corresponding MDALGO setting and related tags.		See table for the corresponding MDALGO setting and related tags.

Jona at 14:43, 20 July 2022

2022-07-20T14:43:06Z

← Older revision		Revision as of 14:43, 20 July 2022
Line 4:		Line 4:

	There are two choices of thermostats which can be adjusted to set up a [[Molecular dynamics calculations\|molecular-dynamics]] run.		There are two choices of thermostats which can be adjusted to set up a [[Molecular dynamics calculations\|molecular-dynamics]] run.
	The [[Andersen thermostat]] can be used by setting the collision probability ({{TAG\|ANDERSEN_PROB}}) with the fictitious heat bath to zero and the [[Nose-Hoover thermostat]] by setting the mass of the virtual degree to minus three. Both settings will switch the thermostat of such that the velocities are determined by the [[Hellmann-Feynman forces]] or [[Machine-learned force fields]] only.		The [[Andersen thermostat]] can be used by setting the collision probability ({{TAG\|ANDERSEN_PROB}}) with the fictitious heat bath to zero and the [[Nose-Hoover thermostat]] by setting the mass of the virtual degree of freedom ({TAG\|SMASS}) to minus three. Both settings will switch the thermostat of such that the velocities are determined by the [[Hellmann-Feynman forces]] or [[Machine-learned force fields]] only.
	See table for the corresponding MDALGO setting and related tags.		See table for the corresponding MDALGO setting and related tags.

← Older revision		Revision as of 11:21, 5 August 2022
Line 5:		Line 5:
	There are two choices of thermostats which can be adjusted to set up a [[Molecular dynamics calculations\|molecular-dynamics]] run.		There are two choices of thermostats which can be adjusted to set up a [[Molecular dynamics calculations\|molecular-dynamics]] run.
	The [[Andersen thermostat]] can be used by setting the collision probability ({{TAG\|ANDERSEN_PROB}}) with the fictitious heat bath to zero and the [[Nose-Hoover thermostat]] by setting the mass of the virtual degree of freedom ({{TAG\|SMASS}}) to minus three. Both settings will switch the thermostat off, such that the velocities are determined by the [[Hellmann-Feynman forces]] or [[Machine-learned force fields]] only.		The [[Andersen thermostat]] can be used by setting the collision probability ({{TAG\|ANDERSEN_PROB}}) with the fictitious heat bath to zero and the [[Nose-Hoover thermostat]] by setting the mass of the virtual degree of freedom ({{TAG\|SMASS}}) to minus three. Both settings will switch the thermostat off, such that the velocities are determined by the [[Hellmann-Feynman forces]] or [[Machine-learned force fields]] only.
	See table for the corresponding MDALGO setting and related tags.		See table for the corresponding {{TAG\|MDALGO}} setting and related tags.

	{\|class="wikitable" style="margin:aut		{\|class="wikitable" style="margin:aut