Charge sloshing - Revision history

Csheldon: Capitalize first letter of file/image link target (broken by wiki case-sensitivity change)

2026-07-22T14:50:27Z

Capitalize first letter of file/image link target (broken by wiki case-sensitivity change)

← Older revision		Revision as of 14:50, 22 July 2026
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	[[File:~~sloshing1~~.png\|600px\|thumb\|Fig. 1: A handwaving illustration of charge sloshing.]]		[[File:Sloshing1.png\|600px\|thumb\|Fig. 1: A handwaving illustration of charge sloshing.]]

	A very handwaving illustration of the phenomenon of charge sloshing during the electronic optimization is shown in Fig. 1:		A very handwaving illustration of the phenomenon of charge sloshing during the electronic optimization is shown in Fig. 1:

2024-10-17T09:30:42Z

← Older revision		Revision as of 09:30, 17 October 2024
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	To prevent charge sloshing {{VASP}} uses [[:Category:Density_mixing \| density mixing]] in the [[self-consistency cycle]].		To prevent charge sloshing {{VASP}} uses [[:Category:Density_mixing \| density mixing]] in the [[self-consistency cycle]].

			== Related tags and articles ==
			{{TAG\|ICHARG}}, {{TAG\|AMIX}}, {{TAG\|BMIX}}, {{TAG\|AMIX_MAG}}, {{TAG\|BMIX_MAG}}, [[Troubleshooting electronic convergence]]

	[[Category:Theory]][[Category:Electronic minimization]][[Category:Density mixing]]		[[Category:Theory]][[Category:Electronic minimization]][[Category:Density mixing]]

2024-07-16T07:08:01Z

← Older revision		Revision as of 07:08, 16 July 2024
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	To prevent charge sloshing {{VASP}} uses [[:Category:Density_mixing \| density mixing]] in the [[self-consistency cycle]].		To prevent charge sloshing {{VASP}} uses [[:Category:Density_mixing \| density mixing]] in the [[self-consistency cycle]].

	[[Category:Theory]]		[[Category:Theory]][[Category:Electronic minimization]][[Category:Density mixing]]

2024-07-15T14:50:14Z

← Older revision		Revision as of 14:50, 15 July 2024
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	To prevent charge sloshing {{VASP}} uses [[:Category:Density_mixing \| density mixing]] in the [[self-consistency cycle]].		To prevent charge sloshing {{VASP}} uses [[:Category:Density_mixing \| density mixing]] in the [[self-consistency cycle]].

			[[Category:Theory]]

2024-07-15T14:00:28Z

← Older revision		Revision as of 14:00, 15 July 2024
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	To prevent charge sloshing {{VASP}} uses [[density mixing]] in the [[self-consistency cycle]].		To prevent charge sloshing {{VASP}} uses [[:Category:Density_mixing \| density mixing]] in the [[self-consistency cycle]].

2024-07-15T13:43:35Z

← Older revision		Revision as of 13:43, 15 July 2024
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	* The aformentioned change in the orbitals leads to a ''long-wavelength'' change in the charge density:		* The aformentioned change in the orbitals leads to a ''long-wavelength'' change in the charge density:

	::<math>\rho({\bf r})=2 \Delta {\rm Re}\, e^{i 2 \delta{\bf k}\cdot{\bf r}}</math>		::<math>\delta\rho({\bf r})=2 \Delta {\rm Re}\, e^{i 2 \delta{\bf k}\cdot{\bf r}}</math>

	:and the consequent change in the Hartree potential due to this long-wavelength change in the density is given by:		:and the consequent change in the Hartree potential due to this long-wavelength change in the density is given by:

	::<math>V_{\rm H}({\bf r})=2 \Delta \frac{4 \pi e^2}{ \| 2\delta {\bf k}\|^2}{\rm Re} \,e^{i 2 \delta{\bf k}\cdot{\bf r}}.</math>		::<math>\delta V_{\rm H}({\bf r})=2 \Delta \frac{4 \pi e^2}{ \| 2\delta {\bf k}\|^2}{\rm Re} \,e^{i 2 \delta{\bf k}\cdot{\bf r}}.</math>

	:The factor <math>1/\|\delta {\bf k}\|^2</math> in the above is in fact the principal origin of charge sloshing: ''a long-wavelength change in the charge density leads to a strongly amplified change in the electrostatic potential.''		:The factor <math>1/\|\delta {\bf k}\|^2</math> in the above is in fact the principal origin of charge sloshing: ''a long-wavelength change in the charge density leads to a strongly amplified change in the electrostatic potential.''

2024-07-15T09:58:11Z

← Older revision		Revision as of 09:58, 15 July 2024
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	:and thus the response in the potential increases with ''L''<sup>2</sup>, the square of the maximum extent of the supercell.		:and thus the response in the potential increases with ''L''<sup>2</sup>, the square of the maximum extent of the supercell.

	:Consequently, the maximum stable step size in a direct optimization algorithm decreases inversely proportional to the square of the maximum extent of the supercell (<math>\Delta = 1/L^2</math>).		:Consequently, the maximum stable step size in a [[Direct_optimization_of_the_orbitals \| direct optimization algorithm]] decreases inversely proportional to the square of the maximum extent of the supercell (<math>\Delta = 1/L^2</math>).

2024-07-15T09:56:12Z

← Older revision		Revision as of 09:56, 15 July 2024
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	To prevent charge sloshing {{VASP}} uses [[density mixing]] in the self-consistency cycle.		To prevent charge sloshing {{VASP}} uses [[density mixing]] in the [[self-consistency cycle]].

2024-07-15T09:55:17Z

← Older revision		Revision as of 09:55, 15 July 2024
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	To prevent charge sloshing {{VASP}} uses [[~~Category:Density_mixing~~ density mixing]] in the self-consistency cycle.		To prevent charge sloshing {{VASP}} uses [[density mixing]] in the self-consistency cycle.

2024-07-15T09:54:45Z

← Older revision		Revision as of 09:54, 15 July 2024
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	To prevent charge sloshing {{VASP}} uses density mixing in the self-consistency cycle.		To prevent charge sloshing {{VASP}} uses [[Category:Density_mixing density mixing]] in the self-consistency cycle.