Troubleshooting electronic convergence - Revision history

Csheldon at 13:19, 24 March 2026

2026-03-24T13:19:55Z

← Older revision		Revision as of 13:19, 24 March 2026
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	There can be many reasons why convergence to the electronic ground state fails. Below you find some general strategies to overcome convergence issues in the [[:Category:Electronic minimization\|electronic minimization]] and some recommendations for specific cases, e.g., charged systems or magnetic systems. This ~~[https~~:~~//youtu.be/v7gc98lG6Wo~~ lecture~~] goes over~~ electronic convergence in VASP.		There can be many reasons why convergence to the electronic ground state fails. Below you find some general strategies to overcome convergence issues in the [[:Category:Electronic minimization\|electronic minimization]] and some recommendations for specific cases, e.g., charged systems or magnetic systems. This {{Video\|electronic:martijn:2021\|lecture covers electronic convergence in VASP}}.

	== Step-by-step instructions ==		== Step-by-step instructions ==

Singraber at 07:58, 24 October 2025

2025-10-24T07:58:11Z

← Older revision		Revision as of 07:58, 24 October 2025
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	'''Step 6:''' For {{TAG\|IALGO}}=5X or 4X change {{TAG\|TIME}}.		'''Step 6:''' For {{TAG\|IALGO}}=5X or 4X change {{TAG\|TIME}}.
	{{NB\|tip\|You can get information at each electronic step using {{~~TAGO~~\|NWRITE\|2,3}}.}}		{{NB\|tip\|You can get information at each electronic step using {{TAG\|NWRITE\|2,3}}.}}

	== Method-specific recommendations ==		== Method-specific recommendations ==

Csheldon at 11:41, 20 October 2025

2025-10-20T11:41:34Z

← Older revision		Revision as of 11:41, 20 October 2025
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	'''Step 6:''' For {{TAG\|IALGO}}=5X or 4X change {{TAG\|TIME}}.		'''Step 6:''' For {{TAG\|IALGO}}=5X or 4X change {{TAG\|TIME}}.
			{{NB\|tip\|You can get information at each electronic step using {{TAGO\|NWRITE\|2,3}}.}}

	== Method-specific recommendations ==		== Method-specific recommendations ==
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	*Restart from partially converged results (stop a calculation after say 20 steps and restart from the {{TAG\|WAVECAR}} file).		*Restart from partially converged results (stop a calculation after say 20 steps and restart from the {{TAG\|WAVECAR}} file).
	*Use constraints to stabilize the magnetic configuration.		*Use constraints to stabilize the magnetic configuration.

			== Related tags and articles ==
			{{TAG\|NWRITE}}

	[[Category:Howto]][[Category:Electronic minimization]]		[[Category:Howto]][[Category:Electronic minimization]]

Csheldon at 10:04, 22 September 2025

2025-09-22T10:04:02Z

← Older revision		Revision as of 10:04, 22 September 2025
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	There can be many reasons why convergence to the electronic ground state fails. Below you find some general strategies to overcome convergence issues in the [[:Category:Electronic minimization\|electronic minimization]] and some recommendations for specific cases, e.g., charged systems or magnetic systems.		There can be many reasons why convergence to the electronic ground state fails. Below you find some general strategies to overcome convergence issues in the [[:Category:Electronic minimization\|electronic minimization]] and some recommendations for specific cases, e.g., charged systems or magnetic systems. This [https://youtu.be/v7gc98lG6Wo lecture] goes over electronic convergence in VASP.

	== Step-by-step instructions ==		== Step-by-step instructions ==

Kaltakm at 14:18, 21 August 2025

2025-08-21T14:18:19Z

← Older revision		Revision as of 14:18, 21 August 2025
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	There can be many reasons why convergence to the electronic ground state fails. Below you find some general strategies to overcome convergence issues in the [[:Category:Electronic minimization\|electronic minimization]] and some recommendations for specific cases, e.g., charged systems or magnetic systems.		There can be many reasons why convergence to the electronic ground state fails. Below you find some general strategies to overcome convergence issues in the [[:Category:Electronic minimization\|electronic minimization]] and some recommendations for specific cases, e.g., charged systems or magnetic systems.

	== Step-by-step instructions ==		== Step-by-step instructions ==

Kaltakm at 14:18, 21 August 2025

2025-08-21T14:18:11Z

← Older revision		Revision as of 14:18, 21 August 2025
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	There can be many reasons why convergence to the electronic ground state fails. Below you find some general strategies to overcome convergence issues in the [[:Category:Electronic minimization\|electronic minimization]] and some recommendations for specific cases, e.g., charged systems or magnetic systems.		There can be many reasons why convergence to the electronic ground state fails. Below you find some general strategies to overcome convergence issues in the [[:Category:Electronic minimization\|electronic minimization]] and some recommendations for specific cases, e.g., charged systems or magnetic systems.

	== Step-by-step instructions ==		== Step-by-step instructions ==

Huebsch at 12:16, 14 October 2024

2024-10-14T12:16:32Z

← Older revision		Revision as of 12:16, 14 October 2024
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	There can be many reasons why convergence to the electronic ground state fails. Below you find some strategies to overcome convergence issues in the [[:Category:Electronic minimization\|electronic minimization]].		There can be many reasons why convergence to the electronic ground state fails. Below you find some general strategies to overcome convergence issues in the [[:Category:Electronic minimization\|electronic minimization]] and some recommendations for specific cases, e.g., charged systems or magnetic systems.

	== Step-by-step instructions ==		== Step-by-step instructions ==

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	# First, converge the calculation with {{TAG\|LDIPOL}}=.FALSE. Store the {{FILE\|WAVECAR}} in the same folder.		# First, converge the calculation with {{TAG\|LDIPOL}}=.FALSE. Store the {{FILE\|WAVECAR}} in the same folder.
	# Use the {{FILE\|WAVECAR}} to restart the calculation with {{TAG\|LDIPOL}}=.TRUE.		# Use the {{FILE\|WAVECAR}} to restart the calculation with {{TAG\|LDIPOL}}=.TRUE.

			=== Magnetic calculations ===

			What can one do when convergence is bad:
			*Start from charge density of non-spin-polarized calculation using {{TAG\|ISTART}}=0 (or remove the {{TAG\|WAVECAR}} file) and {{TAG\|ICHARG}}=1.
			*Use linear mixing by setting {{TAG\|BMIX}}=0.0001 and {{TAG\|BMIX_MAG}}=0.0001.
			*Mix slowly, i.e., reduce {{TAG\|AMIX}} and {{TAG\|AMIX_MAG}}.
			*REDUCE {{TAG\|MAXMIX}}, the number of steps stored in the Broyden mixer (default {{TAG\|MAXMIX}}=45).
			*Restart from partially converged results (stop a calculation after say 20 steps and restart from the {{TAG\|WAVECAR}} file).
			*Use constraints to stabilize the magnetic configuration.

	[[Category:Howto]][[Category:Electronic minimization]]		[[Category:Howto]][[Category:Electronic minimization]]

Svijay: /* Method-specific recommendations */

2024-06-07T14:55:18Z

Method-specific recommendations

← Older revision		Revision as of 14:55, 7 June 2024
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	Similar to the [[#Magnetic calculation with LDA+U\|recipe for magnetic calculation with LDA+U]], it might be helpful to run steps 1. to 3. with a low {{TAG\|ENCUT}} and then perform step 3. again with the desired {{TAG\|ENCUT}}.		Similar to the [[#Magnetic calculation with LDA+U\|recipe for magnetic calculation with LDA+U]], it might be helpful to run steps 1. to 3. with a low {{TAG\|ENCUT}} and then perform step 3. again with the desired {{TAG\|ENCUT}}.

			=== Dipole Correction ===
			# First, converge the calculation with {{TAG\|LDIPOL}}=.FALSE. Store the {{FILE\|WAVECAR}} in the same folder.
			# Use the {{FILE\|WAVECAR}} to restart the calculation with {{TAG\|LDIPOL}}=.TRUE.

	[[Category:Howto]][[Category:Electronic minimization]]		[[Category:Howto]][[Category:Electronic minimization]]

Miranda.henrique: /* Step-by-step instructions */

2023-11-15T06:22:49Z

Step-by-step instructions

← Older revision		Revision as of 06:22, 15 November 2023
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	'''Step 1:''' Simplify the calculation and reduce time-to-solution. Try to create a minimal [[INCAR]] file with as few tags as possible. If the calculation converges, then gradually add them back until you find which one was causing the problem. Try to reduce the time-to-solution as much as possible by lowering the '''k'''-point sampling (or using gamma-only calculations if applicable), lower {{TAG\|ENCUT}}, use {{TAG\|PREC}}=Normal.		'''Step 1:''' Simplify the calculation and reduce time-to-solution. Try to create a minimal [[INCAR]] file with as few tags as possible. If the calculation converges, then gradually add them back until you find which one was causing the problem. Try to reduce the time-to-solution as much as possible by lowering the '''k'''-point sampling (or using gamma-only calculations if applicable), lower {{TAG\|ENCUT}}, use {{TAG\|PREC}}=Normal.

	'''Step 2:''' ~~Fixing~~ the ~~charge density (for cases where density mixing is used)~~		'''Step 2:''' Check the value of {{TAG\|ISMEAR}}. If you have partially occupied states set {{TAG\|ISMEAR}}=-1 or 1.

	'''Step 3:''' ~~Increase {{TAG\|NBANDS}}. Check if you have enough bands. You can do this by looking at~~ the [[OUTCAR]] file and checking that there are enough empty states, i.e., states with zero occupation. When using an iterative solver, the last states might not be accurately described, if these are occupied, then convergence is likely to fail. Often, the VASP default setting for ~~{{TAG\|NBANDS}}~~ is ~~insufficient for systems with f-orbitals or calculations with meta-GGA's.~~		'''Step 3:''' Fixing the charge density (for cases where density mixing is used)

	'''Step 4:''' ~~Switch~~ {{TAG\|~~ALGO~~}}.		'''Step 4:''' Increase {{TAG\|NBANDS}}. Check if you have enough bands. You can do this by looking at the [[OUTCAR]] file and checking that there are enough empty states, i.e., states with zero occupation. When using an iterative solver, the last states might not be accurately described, if these are occupied, then convergence is likely to fail. Often, the VASP default setting for {{TAG\|NBANDS}} is insufficient for systems with f-orbitals or calculations with meta-GGA's.

	'''Step 5:''' For {{TAG\|IALGO}}=5X or 4X change {{TAG\|TIME}}.		'''Step 5:''' Switch {{TAG\|ALGO}}.

			'''Step 6:''' For {{TAG\|IALGO}}=5X or 4X change {{TAG\|TIME}}.

	== Method-specific recommendations ==		== Method-specific recommendations ==

Huebsch at 13:57, 20 October 2023

2023-10-20T13:57:29Z

← Older revision		Revision as of 13:57, 20 October 2023
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	There can be many reasons why convergence to the electronic ground state fails. Below you find some strategies to overcome convergence issues in the [[Category:Electronic minimization\|electronic minimization]].		There can be many reasons why convergence to the electronic ground state fails. Below you find some strategies to overcome convergence issues in the [[:Category:Electronic minimization\|electronic minimization]].
	== Step-by-step instructions ==		== Step-by-step instructions ==

← Older revision		Revision as of 06:22, 15 November 2023
Line 4:		Line 4:
	'''Step 1:''' Simplify the calculation and reduce time-to-solution. Try to create a minimal [[INCAR]] file with as few tags as possible. If the calculation converges, then gradually add them back until you find which one was causing the problem. Try to reduce the time-to-solution as much as possible by lowering the '''k'''-point sampling (or using gamma-only calculations if applicable), lower {{TAG\|ENCUT}}, use {{TAG\|PREC}}=Normal.		'''Step 1:''' Simplify the calculation and reduce time-to-solution. Try to create a minimal [[INCAR]] file with as few tags as possible. If the calculation converges, then gradually add them back until you find which one was causing the problem. Try to reduce the time-to-solution as much as possible by lowering the '''k'''-point sampling (or using gamma-only calculations if applicable), lower {{TAG\|ENCUT}}, use {{TAG\|PREC}}=Normal.

	'''Step 2:''' ~~Fixing~~ the ~~charge density (for cases where density mixing is used)~~		'''Step 2:''' Check the value of {{TAG\|ISMEAR}}. If you have partially occupied states set {{TAG\|ISMEAR}}=-1 or 1.

	'''Step 3:''' ~~Increase {{TAG\|NBANDS}}. Check if you have enough bands. You can do this by looking at~~ the [[OUTCAR]] file and checking that there are enough empty states, i.e., states with zero occupation. When using an iterative solver, the last states might not be accurately described, if these are occupied, then convergence is likely to fail. Often, the VASP default setting for ~~{{TAG\|NBANDS}}~~ is ~~insufficient for systems with f-orbitals or calculations with meta-GGA's.~~		'''Step 3:''' Fixing the charge density (for cases where density mixing is used)

	'''Step 4:''' ~~Switch~~ {{TAG\|~~ALGO~~}}.		'''Step 4:''' Increase {{TAG\|NBANDS}}. Check if you have enough bands. You can do this by looking at the [[OUTCAR]] file and checking that there are enough empty states, i.e., states with zero occupation. When using an iterative solver, the last states might not be accurately described, if these are occupied, then convergence is likely to fail. Often, the VASP default setting for {{TAG\|NBANDS}} is insufficient for systems with f-orbitals or calculations with meta-GGA's.

	'''Step 5:''' For {{TAG\|IALGO}}=5X or 4X change {{TAG\|TIME}}.		'''Step 5:''' Switch {{TAG\|ALGO}}.

			'''Step 6:''' For {{TAG\|IALGO}}=5X or 4X change {{TAG\|TIME}}.

	== Method-specific recommendations ==		== Method-specific recommendations ==