LNONCOLLINEAR - Revision history

Csheldon at 12:56, 15 January 2025

2025-01-15T12:56:19Z

← Older revision		Revision as of 12:56, 15 January 2025
Line 26:		Line 26:

	Supported as of VASP.4.5.		Supported as of VASP.4.5.
	{{NB\|important\| For noncollinear calculations~~, {{TAG\|ISPIN}}{{=}}1 should be used.~~ {{TAG\|ISPIN}}~~{{=}}2 performs collinear calculations, which~~ is ~~incompatible with noncollinear~~. In VASP 6.5.0, the calculation will exit with an error message if {{TAG\|ISPIN}}{{=}}2 is used in combination with the {{TAG\|LNONCOLLINEAR}}{{=}}.TRUE.\|}}		{{NB\|important\| For noncollinear calculations {{TAG\|ISPIN}} is ignored. In VASP 6.5.0, the calculation will exit with an error message if {{TAG\|ISPIN}}{{=}}2 and {{TAG\|MAGMOM}} is used in combination with the {{TAG\|LNONCOLLINEAR}}{{=}}.TRUE.\|}}

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

Csheldon at 12:08, 15 January 2025

2025-01-15T12:08:38Z

← Older revision		Revision as of 12:08, 15 January 2025
Line 26:		Line 26:

	Supported as of VASP.4.5.		Supported as of VASP.4.5.
	{{NB\|important\| For noncollinear calculations, {{TAG\|ISPIN}}{{=}}1 should be used. {{TAG\|ISPIN}}{{=}}2 performs collinear calculations, which is incompatible with noncollinear. In VASP 6.5.0, the calculation will ~~crash~~ if {{TAG\|ISPIN}}{{=}}2 is used in combination with the {{TAG\|LNONCOLLINEAR}}{{=}}.TRUE.\|}}		{{NB\|important\| For noncollinear calculations, {{TAG\|ISPIN}}{{=}}1 should be used. {{TAG\|ISPIN}}{{=}}2 performs collinear calculations, which is incompatible with noncollinear. In VASP 6.5.0, the calculation will exit with an error message if {{TAG\|ISPIN}}{{=}}2 is used in combination with the {{TAG\|LNONCOLLINEAR}}{{=}}.TRUE.\|}}

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

Csheldon at 10:48, 10 January 2025

2025-01-10T10:48:33Z

← Older revision		Revision as of 10:48, 10 January 2025
Line 26:		Line 26:

	Supported as of VASP.4.5.		Supported as of VASP.4.5.
	{{NB\|important\| For noncollinear calculations, {{TAG\|ISPIN}}{{=}}1 should be used. {{TAG\|ISPIN}}{{=}}2 performs collinear calculations, which noncollinear ~~make redundant~~. In VASP 6.5.0, the calculation will crash if {{TAG\|ISPIN}}{{=}}2 is used in combination with the {{TAG\|LNONCOLLINEAR}}{{=}}.TRUE.\|}}		{{NB\|important\| For noncollinear calculations, {{TAG\|ISPIN}}{{=}}1 should be used. {{TAG\|ISPIN}}{{=}}2 performs collinear calculations, which is incompatible with noncollinear. In VASP 6.5.0, the calculation will crash if {{TAG\|ISPIN}}{{=}}2 is used in combination with the {{TAG\|LNONCOLLINEAR}}{{=}}.TRUE.\|}}

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

Csheldon at 09:35, 9 January 2025

2025-01-09T09:35:53Z

← Older revision		Revision as of 09:35, 9 January 2025
Line 26:		Line 26:

	Supported as of VASP.4.5.		Supported as of VASP.4.5.

	{{NB\|important\| For noncollinear calculations, {{TAG\|ISPIN}}{{=}}1 should be used. {{TAG\|ISPIN}}{{=}}2 performs collinear calculations, which noncollinear make redundant. In VASP 6.5.0, the calculation will crash if {{TAG\|ISPIN}}{{=}}2 is used in combination with the {{TAG\|LNONCOLLINEAR}}{{=}}.TRUE.\|}}		{{NB\|important\| For noncollinear calculations, {{TAG\|ISPIN}}{{=}}1 should be used. {{TAG\|ISPIN}}{{=}}2 performs collinear calculations, which noncollinear make redundant. In VASP 6.5.0, the calculation will crash if {{TAG\|ISPIN}}{{=}}2 is used in combination with the {{TAG\|LNONCOLLINEAR}}{{=}}.TRUE.\|}}

Csheldon at 09:35, 9 January 2025

2025-01-09T09:35:44Z

← Older revision		Revision as of 09:35, 9 January 2025
Line 26:		Line 26:

	Supported as of VASP.4.5.		Supported as of VASP.4.5.

			{{NB\|important\| For noncollinear calculations, {{TAG\|ISPIN}}{{=}}1 should be used. {{TAG\|ISPIN}}{{=}}2 performs collinear calculations, which noncollinear make redundant. In VASP 6.5.0, the calculation will crash if {{TAG\|ISPIN}}{{=}}2 is used in combination with the {{TAG\|LNONCOLLINEAR}}{{=}}.TRUE.\|}}

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

Huebsch at 12:25, 26 September 2023

2023-09-26T12:25:02Z

← Older revision		Revision as of 12:25, 26 September 2023
Line 1:		Line 1:
	{{TAGDEF\|LNONCOLLINEAR\|.~~TRUE~~. {{!}} .~~FALSE~~.\|.~~FALSE~~.}}		{{TAGDEF\|LNONCOLLINEAR\|.True. {{!}} .False.}}
			{{DEF\|LNONCOLLINEAR\|.False.\| \|.True.\|if spin-orbit coupling is included ({{TAG\|LSORBIT}}{{=}}.True.)}}

	Description: ~~{{TAG\|LNONCOLLINEAR}} specifies whether fully non-collinear~~ magnetic calculations ~~are performed~~.		Description: Switch on noncollinear magnetic calculations.
	----		----
	~~Supported as of VASP.4.5.~~

	~~Setting~~ {{TAG\|LNONCOLLINEAR}} = ~~.TRUE.~~ in the {{TAG\|INCAR}} file ~~allows~~ to ~~perform fully non~~-~~collinear~~ magnetic ~~structure calculations~~. ~~VASP~~ is ~~capable of~~ reading {{TAG\|WAVECAR}} ~~and~~ {{TAG\|CHGCAR}} files ~~from previous non~~-~~magnetic or collinear calculations, it~~ is ~~however~~ not possible to rotate the magnetic ~~field~~ locally on selected atoms.		For noncollinear magnetic calculations, set {{TAG\|LNONCOLLINEAR}} = True in the {{TAG\|INCAR}} file and use the <code>vasp_ncl</code> executable. The electronic minimization treats the full 2x2 spin density{{Cite\|hobbs:prb:00}}

			:<math>
			n_{\sigma\sigma'}(\mathbf{r}) = \sum_{n=1}^N \psi_{n\sigma}(\mathbf{r})\psi^*_{n\sigma'}(\mathbf{r}),
			</math>
			which is written to the {{FILE\|CHGCAR}} file. In spinor space, the part of the spin density proportional to the 2x2 unit matrix corresponds to the charge density, and the part proportional to the vector of Pauli matrices is the magnetization density.
			This enables the consideration of noncollinear magnetic structures within spin-density-functional theory. {{TAG\|MAGMOM}} sets the initial magnetic moments. Write the final magnetic moments by setting {{TAG\|LORBIT}}.

			It is possible to '''restart a noncollinear calculation''' from a previous nonmagnetic calculation ({{TAG\|ISPIN}}=1 and {{TAG\|LNONCOLLINEAR}}=F) or spin-polarized calculation ({{TAG\|ISPIN}}=2) by reading {{TAG\|WAVECAR}} or {{TAG\|CHGCAR}} files. The magnetization of the spin-polarized calculation is interpreted to point along {{TAG\|SAXIS}} (default: Cartesian direction <math>\hat z</math>). It is not possible to rotate the magnetic moment locally on selected atoms when restarting with a magnetization density. The magnetic configuration can globally be rotated with respect to the lattice by restarting with a different {{TAG\|SAXIS}}.

			In practice, we recommend performing noncollinear calculations in two steps:
			*First, calculate the nonmagnetic ground state and generate a {{FILE\|WAVECAR}} and a {{FILE\|CHGCAR}} file.
			*Second, read the {{TAG\|WAVECAR}} and {{TAG\|CHGCAR}} file, and supply initial magnetic moments using the {{TAG\|MAGMOM}} tag.

	~~Hence, in practice, we~~ recommend ~~to perform non-collinear calculations in two steps:~~		We recommend setting {{TAG\|GGA_COMPAT}} = False and {{TAG\|LASPH}}= True for noncollinear calculations since this improves the numerical precision of calculations using the generalized-gradient approximation (GGA).
	*First, calculate the non magnetic groundstate and generate a {{TAG\|~~WAVECAR~~}} and {{TAG\|~~CHGCAR~~}} ~~file.~~
	*Second, read the ~~{{TAG\|WAVECAR}} and {{TAG\|CHGCAR}} file, and supply initial magnetic moments by means~~ of the ~~{{TAG\|MAGMOM}} tag~~ (~~compare {{TAG\|MAGMOM}}~~).

	~~For a non-collinear setup, three values must be supplied for each ion in the~~ {{TAG\|~~MAGMOM~~}} ~~line. The three entries correspond to the initial local magnetic moment~~ for ~~each ion in x, y and z direction respectively~~. ~~The line~~		Consider setting {{TAG\|AMIX_MAG}} and {{TAG\|BMIX_MAG}} for better convergence when using [[Density mixing\|density mixing]].

	~~MAGMOM = 1 0 0 0 1 0~~		The {{TAG\|I_CONSTRAINED_M}} tag can constrain the on-site magnetic moments.

	~~initialises the magnetic moment on the first atom in the x-direction, and on the second atom in the y direction~~. ~~Mind, that the {{TAG\|MAGMOM}} line supplies initial magnetic moments only if {{TAG\|ICHARG}} = 2, or if the {{TAG\|CHGCAR}} file contains only charge but no magnetisation density~~.		Supported as of VASP.4.5.

	== Related tags and articles ==		== Related tags and articles ==
	{{TAG\|MAGMOM}},		{{TAG\|MAGMOM}},
	{{TAG\|~~ICHARG~~}},		{{TAG\|LSORBIT}},
	{{TAG\|~~LSORBIT~~}}		{{TAG\|SAXIS}},
			{{TAG\|GGA_COMPAT}},
			{{TAG\|LASPH}},
			{{TAG\|AMIX_MAG}}, {{TAG\|BMIX_MAG}},


	{{sc\|LNONCOLLINEAR\|Examples\|Examples that use this tag}}		{{sc\|LNONCOLLINEAR\|Examples\|Examples that use this tag}}

Karsai: /* Related Tags and Sections */

2022-04-08T14:37:01Z

Related Tags and Sections

← Older revision		Revision as of 14:37, 8 April 2022
Line 17:		Line 17:
	initialises the magnetic moment on the first atom in the x-direction, and on the second atom in the y direction. Mind, that the {{TAG\|MAGMOM}} line supplies initial magnetic moments only if {{TAG\|ICHARG}} = 2, or if the {{TAG\|CHGCAR}} file contains only charge but no magnetisation density.		initialises the magnetic moment on the first atom in the x-direction, and on the second atom in the y direction. Mind, that the {{TAG\|MAGMOM}} line supplies initial magnetic moments only if {{TAG\|ICHARG}} = 2, or if the {{TAG\|CHGCAR}} file contains only charge but no magnetisation density.

	== Related ~~Tags~~ and ~~Sections~~ ==		== Related tags and articles ==
	{{TAG\|MAGMOM}},		{{TAG\|MAGMOM}},
	{{TAG\|ICHARG}},		{{TAG\|ICHARG}},
Line 25:		Line 25:
	----		----

	[[Category:INCAR]][[Category:Magnetism]][[Category:Noncollinear magnetism]]		[[Category:INCAR tag]][[Category:Magnetism]][[Category:Noncollinear magnetism]]

Karsai: /* Related Tags and Sections */

2019-11-18T12:19:10Z

Related Tags and Sections

← Older revision		Revision as of 12:19, 18 November 2019
Line 24:		Line 24:
	{{sc\|LNONCOLLINEAR\|Examples\|Examples that use this tag}}		{{sc\|LNONCOLLINEAR\|Examples\|Examples that use this tag}}
	----		----
	~~[[The_VASP_Manual\|Contents]]~~

	[[Category:INCAR]][[Category:Magnetism]][[Category:Noncollinear magnetism]]		[[Category:INCAR]][[Category:Magnetism]][[Category:Noncollinear magnetism]]

Karsai at 15:26, 11 March 2019

2019-03-11T15:26:21Z

← Older revision		Revision as of 15:26, 11 March 2019
Line 26:		Line 26:
	[[The_VASP_Manual\|Contents]]		[[The_VASP_Manual\|Contents]]

	[[Category:INCAR]][[Category:Magnetism]]		[[Category:INCAR]][[Category:Magnetism]][[Category:Noncollinear magnetism]]

Karsai at 10:19, 20 March 2017

2017-03-20T10:19:57Z

← Older revision		Revision as of 10:19, 20 March 2017
Line 22:		Line 22:
	{{TAG\|LSORBIT}}		{{TAG\|LSORBIT}}

	~~== Example Calculations using this Tag ==~~		{{sc\|LNONCOLLINEAR\|Examples\|Examples that use this tag}}
	{{~~TAG~~\|~~constraining local magnetic moments}}, {{TAG~~\|~~Spin-orbit coupling in a Fe monolayer}}, {{TAG~~\|~~Spin-orbit coupling in a Ni monolayer~~}}
	----		----
	[[The_VASP_Manual\|Contents]]		[[The_VASP_Manual\|Contents]]

	[[Category:INCAR]][[Category:Magnetism]]		[[Category:INCAR]][[Category:Magnetism]]

← Older revision		Revision as of 12:25, 26 September 2023
Line 1:		Line 1:
	{{TAGDEF\|LNONCOLLINEAR\|.~~TRUE~~. {{!}} .~~FALSE~~.\|.~~FALSE~~.}}		{{TAGDEF\|LNONCOLLINEAR\|.True. {{!}} .False.}}
			{{DEF\|LNONCOLLINEAR\|.False.\| \|.True.\|if spin-orbit coupling is included ({{TAG\|LSORBIT}}{{=}}.True.)}}

	Description: ~~{{TAG\|LNONCOLLINEAR}} specifies whether fully non-collinear~~ magnetic calculations ~~are performed~~.		Description: Switch on noncollinear magnetic calculations.
	----		----
	~~Supported as of VASP.4.5.~~

	~~Setting~~ {{TAG\|LNONCOLLINEAR}} = ~~.TRUE.~~ in the {{TAG\|INCAR}} file ~~allows~~ to ~~perform fully non~~-~~collinear~~ magnetic ~~structure calculations~~. ~~VASP~~ is ~~capable of~~ reading {{TAG\|WAVECAR}} ~~and~~ {{TAG\|CHGCAR}} files ~~from previous non~~-~~magnetic or collinear calculations, it~~ is ~~however~~ not possible to rotate the magnetic ~~field~~ locally on selected atoms.		For noncollinear magnetic calculations, set {{TAG\|LNONCOLLINEAR}} = True in the {{TAG\|INCAR}} file and use the <code>vasp_ncl</code> executable. The electronic minimization treats the full 2x2 spin density{{Cite\|hobbs:prb:00}}

			:<math>
			n_{\sigma\sigma'}(\mathbf{r}) = \sum_{n=1}^N \psi_{n\sigma}(\mathbf{r})\psi^*_{n\sigma'}(\mathbf{r}),
			</math>
			which is written to the {{FILE\|CHGCAR}} file. In spinor space, the part of the spin density proportional to the 2x2 unit matrix corresponds to the charge density, and the part proportional to the vector of Pauli matrices is the magnetization density.
			This enables the consideration of noncollinear magnetic structures within spin-density-functional theory. {{TAG\|MAGMOM}} sets the initial magnetic moments. Write the final magnetic moments by setting {{TAG\|LORBIT}}.

			It is possible to '''restart a noncollinear calculation''' from a previous nonmagnetic calculation ({{TAG\|ISPIN}}=1 and {{TAG\|LNONCOLLINEAR}}=F) or spin-polarized calculation ({{TAG\|ISPIN}}=2) by reading {{TAG\|WAVECAR}} or {{TAG\|CHGCAR}} files. The magnetization of the spin-polarized calculation is interpreted to point along {{TAG\|SAXIS}} (default: Cartesian direction <math>\hat z</math>). It is not possible to rotate the magnetic moment locally on selected atoms when restarting with a magnetization density. The magnetic configuration can globally be rotated with respect to the lattice by restarting with a different {{TAG\|SAXIS}}.

			In practice, we recommend performing noncollinear calculations in two steps:
			*First, calculate the nonmagnetic ground state and generate a {{FILE\|WAVECAR}} and a {{FILE\|CHGCAR}} file.
			*Second, read the {{TAG\|WAVECAR}} and {{TAG\|CHGCAR}} file, and supply initial magnetic moments using the {{TAG\|MAGMOM}} tag.

	~~Hence, in practice, we~~ recommend ~~to perform non-collinear calculations in two steps:~~		We recommend setting {{TAG\|GGA_COMPAT}} = False and {{TAG\|LASPH}}= True for noncollinear calculations since this improves the numerical precision of calculations using the generalized-gradient approximation (GGA).
	*First, calculate the non magnetic groundstate and generate a {{TAG\|~~WAVECAR~~}} and {{TAG\|~~CHGCAR~~}} ~~file.~~
	*Second, read the ~~{{TAG\|WAVECAR}} and {{TAG\|CHGCAR}} file, and supply initial magnetic moments by means~~ of the ~~{{TAG\|MAGMOM}} tag~~ (~~compare {{TAG\|MAGMOM}}~~).

	~~For a non-collinear setup, three values must be supplied for each ion in the~~ {{TAG\|~~MAGMOM~~}} ~~line. The three entries correspond to the initial local magnetic moment~~ for ~~each ion in x, y and z direction respectively~~. ~~The line~~		Consider setting {{TAG\|AMIX_MAG}} and {{TAG\|BMIX_MAG}} for better convergence when using [[Density mixing\|density mixing]].

	~~MAGMOM = 1 0 0 0 1 0~~		The {{TAG\|I_CONSTRAINED_M}} tag can constrain the on-site magnetic moments.

	~~initialises the magnetic moment on the first atom in the x-direction, and on the second atom in the y direction~~. ~~Mind, that the {{TAG\|MAGMOM}} line supplies initial magnetic moments only if {{TAG\|ICHARG}} = 2, or if the {{TAG\|CHGCAR}} file contains only charge but no magnetisation density~~.		Supported as of VASP.4.5.

	== Related tags and articles ==		== Related tags and articles ==
	{{TAG\|MAGMOM}},		{{TAG\|MAGMOM}},
	{{TAG\|~~ICHARG~~}},		{{TAG\|LSORBIT}},
	{{TAG\|~~LSORBIT~~}}		{{TAG\|SAXIS}},
			{{TAG\|GGA_COMPAT}},
			{{TAG\|LASPH}},
			{{TAG\|AMIX_MAG}}, {{TAG\|BMIX_MAG}},


	{{sc\|LNONCOLLINEAR\|Examples\|Examples that use this tag}}		{{sc\|LNONCOLLINEAR\|Examples\|Examples that use this tag}}