LCHIMAG - Revision history

Csheldon: /* Chemical shielding */

2026-03-10T13:57:12Z

Chemical shielding

← Older revision		Revision as of 13:57, 10 March 2026
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	Next, the tensor is processed and its chemical shielding anisotropy (CSA) characteristics are printed in the {{FILE\|OUTCAR}}. The tensor is symmetrized (<math>\sigma_{ij} = \sigma_{ji}</math> is enforced) and diagonalized. From the three diagonal values the isotropic chemical "shift" <math>\delta_{\mathrm{iso}}\mathrm{[VASP]}</math>, span <math>\Omega</math>, and skew <math>\kappa</math> are calculated and printed see Ref. {{Cite\|mason:ssn:1993}} for unambiguous definitions. Note that <math>\kappa</math> is ill-defined if <math>\Omega = 0</math>. Units are ppm, except for the skew. A typical output is given below:		Next, the tensor is processed and its chemical shielding anisotropy (CSA) characteristics are printed in the {{FILE\|OUTCAR}}. The tensor is symmetrized (<math>\sigma_{ij} = \sigma_{ji}</math> is enforced) and diagonalized. From the three diagonal values the isotropic chemical "shift" <math>\delta_{\mathrm{iso}}\mathrm{[VASP]}</math>, span <math>\Omega</math>, and skew <math>\kappa</math> are calculated and printed see Ref. {{Cite\|mason:ssn:1993}} for unambiguous definitions. Note that <math>\kappa</math> is ill-defined if <math>\Omega = 0</math>. Units are ppm, except for the skew. A typical output is given below:
	{{NB\|mind\|As of VASP 6.6.0, the following is legacy format (cf. {{TAG\|LNMRLEG}}.}}		{{NB\|mind\|As of VASP 6.6.0, the following is legacy format (cf. {{TAG\|LNMRLEG}}).}}

	<pre>		<pre>

Csheldon at 13:56, 10 March 2026

2026-03-10T13:56:20Z

← Older revision		Revision as of 13:56, 10 March 2026
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	----		----
	For {{TAG\|LCHIMAG\|True}}, the chemical shift tensors and magnetic susceptibility is computed. The implementation{{Cite\|dewijs:laskowski:jcp:2017}} is based on linear response theory using the gauge-invariant PAW method of Yates, Pickard, and Mauri {{Cite\|pickard:prb:2001}}{{Cite\|yates:prb:2007}}, that is an extension to the standard [[PAW method]] to account for the effects of a vector gauge field <math>A</math>. The NMR response currents are computed and the induced B field is calculated based on the Biot-Savart law.		For {{TAG\|LCHIMAG\|True}}, the chemical shift tensors and magnetic susceptibility is computed. The implementation{{Cite\|dewijs:laskowski:jcp:2017}} is based on linear response theory using the gauge-invariant PAW method of Yates, Pickard, and Mauri {{Cite\|pickard:prb:2001}}{{Cite\|yates:prb:2007}}, that is an extension to the standard [[PAW method]] to account for the effects of a vector gauge field <math>A</math>. The NMR response currents are computed and the induced B field is calculated based on the Biot-Savart law.
	~~<!--~~
	See also {{TAG\|WRT_NMRCUR}} to write the currents and {{TAG\|NUCIND}} to compute the nucleus-independent chemical shielding (NICS).		See also {{TAG\|WRT_NMRCUR}} to write the currents and {{TAG\|NUCIND}} to compute the nucleus-independent chemical shielding (NICS).
	{{NB\|warning\|This method only works for non-metallic systems, i.e., that have a finite bandgap.}}~~-->~~		{{NB\|warning\|This method only works for non-metallic systems, i.e., that have a finite bandgap.}}

	Follow these guides for [[Calculating the chemical shieldings\|calculating the chemical shieldings]] and [[Calculating the magnetic susceptibility\|calculating the magnetic susceptibility]].		Follow these guides for [[Calculating the chemical shieldings\|calculating the chemical shieldings]] and [[Calculating the magnetic susceptibility\|calculating the magnetic susceptibility]].
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	Next, the tensor is processed and its chemical shielding anisotropy (CSA) characteristics are printed in the {{FILE\|OUTCAR}}. The tensor is symmetrized (<math>\sigma_{ij} = \sigma_{ji}</math> is enforced) and diagonalized. From the three diagonal values the isotropic chemical "shift" <math>\delta_{\mathrm{iso}}\mathrm{[VASP]}</math>, span <math>\Omega</math>, and skew <math>\kappa</math> are calculated and printed see Ref. {{Cite\|mason:ssn:1993}} for unambiguous definitions. Note that <math>\kappa</math> is ill-defined if <math>\Omega = 0</math>. Units are ppm, except for the skew. A typical output is given below:		Next, the tensor is processed and its chemical shielding anisotropy (CSA) characteristics are printed in the {{FILE\|OUTCAR}}. The tensor is symmetrized (<math>\sigma_{ij} = \sigma_{ji}</math> is enforced) and diagonalized. From the three diagonal values the isotropic chemical "shift" <math>\delta_{\mathrm{iso}}\mathrm{[VASP]}</math>, span <math>\Omega</math>, and skew <math>\kappa</math> are calculated and printed see Ref. {{Cite\|mason:ssn:1993}} for unambiguous definitions. Note that <math>\kappa</math> is ill-defined if <math>\Omega = 0</math>. Units are ppm, except for the skew. A typical output is given below:
			{{NB\|mind\|As of VASP 6.6.0, the following is legacy format (cf. {{TAG\|LNMRLEG}}.}}

	<pre>		<pre>
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	*The lower block has the contributions due to the frozen PAW cores added. These core contributions are rigid {{Cite\|gregor:jcp:1999}}. They depend on {{FILE\|POTCAR}} and are isotropic, i.e. affect neither SPAN nor SKEW.}}		*The lower block has the contributions due to the frozen PAW cores added. These core contributions are rigid {{Cite\|gregor:jcp:1999}}. They depend on {{FILE\|POTCAR}} and are isotropic, i.e. affect neither SPAN nor SKEW.}}

	As of VASP.6.6.0 on OUTCAR ~~also~~ a summary of the tensors per ion is printed. This is done both excluding and including the '''G'''=0 contribution.		As of VASP.6.6.0, in {{FILE\|OUTCAR}} a summary of the tensors per ion is also printed. This is done both excluding and including the '''G'''=0 contribution.
	The summary starts with, for each ion, its number, the isotropic shielding, the shielding tensor and the symmetrized shielding tensor.		The summary starts with, for each ion, its number, the isotropic shielding, the shielding tensor and the symmetrized shielding tensor.
	Next the principal components and the principal axes are printed (from the symmetrized tensor).		Next the principal components and the principal axes are printed (from the symmetrized tensor).

Csheldon: /* Chemical shielding */

2026-03-10T13:53:41Z

Chemical shielding

← Older revision		Revision as of 13:53, 10 March 2026
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	*The upper block gives the shielding due to only the electrons included in the SCF calculation.		*The upper block gives the shielding due to only the electrons included in the SCF calculation.
	*The lower block has the contributions due to the frozen PAW cores added. These core contributions are rigid {{Cite\|gregor:jcp:1999}}. They depend on {{FILE\|POTCAR}} and are isotropic, i.e. affect neither SPAN nor SKEW.}}		*The lower block has the contributions due to the frozen PAW cores added. These core contributions are rigid {{Cite\|gregor:jcp:1999}}. They depend on {{FILE\|POTCAR}} and are isotropic, i.e. affect neither SPAN nor SKEW.}}
	~~<!--~~
	As of VASP.6.5.2 on OUTCAR also a summary of the tensors per ion is printed. This is done both excluding and including the '''G'''=0 contribution.		As of VASP.6.6.0 on OUTCAR also a summary of the tensors per ion is printed. This is done both excluding and including the '''G'''=0 contribution.
	The summary starts with, for each ion, its number, the isotropic shielding, the shielding tensor and the symmetrized shielding tensor.		The summary starts with, for each ion, its number, the isotropic shielding, the shielding tensor and the symmetrized shielding tensor.
	Next the principal components and the principal axes are printed (from the symmetrized tensor).		Next the principal components and the principal axes are printed (from the symmetrized tensor).
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	---------------------------------------------------------------------------------------		---------------------------------------------------------------------------------------
	</pre>		</pre>
	~~-->~~

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

Singraber at 07:46, 24 October 2025

2025-10-24T07:46:24Z

← Older revision		Revision as of 07:46, 24 October 2025
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	Description: Calculate the chemical shifts and magnetic susceptibility within linear response theory.		Description: Calculate the chemical shifts and magnetic susceptibility within linear response theory.
	----		----
	For {{~~TAGO~~\|LCHIMAG\|True}}, the chemical shift tensors and magnetic susceptibility is computed. The implementation{{Cite\|dewijs:laskowski:jcp:2017}} is based on linear response theory using the gauge-invariant PAW method of Yates, Pickard, and Mauri {{Cite\|pickard:prb:2001}}{{Cite\|yates:prb:2007}}, that is an extension to the standard [[PAW method]] to account for the effects of a vector gauge field <math>A</math>. The NMR response currents are computed and the induced B field is calculated based on the Biot-Savart law.		For {{TAG\|LCHIMAG\|True}}, the chemical shift tensors and magnetic susceptibility is computed. The implementation{{Cite\|dewijs:laskowski:jcp:2017}} is based on linear response theory using the gauge-invariant PAW method of Yates, Pickard, and Mauri {{Cite\|pickard:prb:2001}}{{Cite\|yates:prb:2007}}, that is an extension to the standard [[PAW method]] to account for the effects of a vector gauge field <math>A</math>. The NMR response currents are computed and the induced B field is calculated based on the Biot-Savart law.
	<!--		<!--
	See also {{TAG\|WRT_NMRCUR}} to write the currents and {{TAG\|NUCIND}} to compute the nucleus-independent chemical shielding (NICS).		See also {{TAG\|WRT_NMRCUR}} to write the currents and {{TAG\|NUCIND}} to compute the nucleus-independent chemical shielding (NICS).
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	</math>		</math>
	Here, <math>\sigma_{ij}^{\mathrm{ref}}</math> is the isotropic shielding of the nucleus in the reference compound. <math>\delta_{ij}(\mathbf{R})</math> is the chemical shift tensor. In order to compare numerical results with the experimental data, one usually considers a series of compounds and references them to the experimental series.		Here, <math>\sigma_{ij}^{\mathrm{ref}}</math> is the isotropic shielding of the nucleus in the reference compound. <math>\delta_{ij}(\mathbf{R})</math> is the chemical shift tensor. In order to compare numerical results with the experimental data, one usually considers a series of compounds and references them to the experimental series.
	<!--{{NB\|mind\|If VASP reports the chemical shift ({{~~TAGO~~\|LNMRSHIELD\|False}}) it is simply the negative shielding, <math>\delta_{ij}(\mathbf{R})= - \sigma_{ij}(\mathbf{R})</math>. The reference must still be added in the postprocessing to analyze the data.}}-->		<!--{{NB\|mind\|If VASP reports the chemical shift ({{TAG\|LNMRSHIELD\|False}}) it is simply the negative shielding, <math>\delta_{ij}(\mathbf{R})= - \sigma_{ij}(\mathbf{R})</math>. The reference must still be added in the postprocessing to analyze the data.}}-->

	VASP calculates chemical "shifts" for non-metallic crystalline systems using the linear response method of Yates, Pickard, and Mauri {{Cite\|pickard:prb:2001}}{{Cite\|yates:prb:2007}}.		VASP calculates chemical "shifts" for non-metallic crystalline systems using the linear response method of Yates, Pickard, and Mauri {{Cite\|pickard:prb:2001}}{{Cite\|yates:prb:2007}}.

Csheldon at 15:44, 26 May 2025

2025-05-26T15:44:35Z

← Older revision		Revision as of 15:44, 26 May 2025
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	\delta_{ij}(\mathbf{R}) = \sigma_{ij}^{\mathrm{ref}} - \sigma_{ij}(\mathbf{R})		\delta_{ij}(\mathbf{R}) = \sigma_{ij}^{\mathrm{ref}} - \sigma_{ij}(\mathbf{R})
	</math>		</math>
	Here, <math>\sigma_{ij}^{\mathrm{ref}}</math> is the isotropic shielding of the nucleus in the reference compound. <math>\delta_{ij}(\mathbf{R})</math> is the chemical shift tensor. In order to compare numerical results with the experimental data, one usually considers a series of compounds and references ~~that~~ to the experimental series.		Here, <math>\sigma_{ij}^{\mathrm{ref}}</math> is the isotropic shielding of the nucleus in the reference compound. <math>\delta_{ij}(\mathbf{R})</math> is the chemical shift tensor. In order to compare numerical results with the experimental data, one usually considers a series of compounds and references them to the experimental series.
	{{NB\|mind\|If VASP reports the chemical shift ({{TAGO\|LNMRSHIELD\|False}}) it is simply the negative shielding, <math>\delta_{ij}(\mathbf{R})= - \sigma_{ij}(\mathbf{R})</math>. The reference must still be added in the postprocessing to analyze the data.}}		<!--{{NB\|mind\|If VASP reports the chemical shift ({{TAGO\|LNMRSHIELD\|False}}) it is simply the negative shielding, <math>\delta_{ij}(\mathbf{R})= - \sigma_{ij}(\mathbf{R})</math>. The reference must still be added in the postprocessing to analyze the data.}}-->

	VASP calculates chemical "shifts" for non-metallic crystalline systems using the linear response method of Yates, Pickard, and Mauri {{Cite\|pickard:prb:2001}}{{Cite\|yates:prb:2007}}.		VASP calculates chemical "shifts" for non-metallic crystalline systems using the linear response method of Yates, Pickard, and Mauri {{Cite\|pickard:prb:2001}}{{Cite\|yates:prb:2007}}.

Csheldon at 15:33, 26 May 2025

2025-05-26T15:33:11Z

← Older revision		Revision as of 15:33, 26 May 2025
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	----		----
	For {{TAGO\|LCHIMAG\|True}}, the chemical shift tensors and magnetic susceptibility is computed. The implementation{{Cite\|dewijs:laskowski:jcp:2017}} is based on linear response theory using the gauge-invariant PAW method of Yates, Pickard, and Mauri {{Cite\|pickard:prb:2001}}{{Cite\|yates:prb:2007}}, that is an extension to the standard [[PAW method]] to account for the effects of a vector gauge field <math>A</math>. The NMR response currents are computed and the induced B field is calculated based on the Biot-Savart law.		For {{TAGO\|LCHIMAG\|True}}, the chemical shift tensors and magnetic susceptibility is computed. The implementation{{Cite\|dewijs:laskowski:jcp:2017}} is based on linear response theory using the gauge-invariant PAW method of Yates, Pickard, and Mauri {{Cite\|pickard:prb:2001}}{{Cite\|yates:prb:2007}}, that is an extension to the standard [[PAW method]] to account for the effects of a vector gauge field <math>A</math>. The NMR response currents are computed and the induced B field is calculated based on the Biot-Savart law.
			<!--
	See also {{TAG\|WRT_NMRCUR}} to write the currents and {{TAG\|NUCIND}} to compute the nucleus-independent chemical shielding (NICS).		See also {{TAG\|WRT_NMRCUR}} to write the currents and {{TAG\|NUCIND}} to compute the nucleus-independent chemical shielding (NICS).
	{{NB\|warning\|This method only works for non-metallic systems, i.e., that have a finite bandgap.}}		{{NB\|warning\|This method only works for non-metallic systems, i.e., that have a finite bandgap.}}-->

	Follow these guides for [[Calculating the chemical shieldings\|calculating the chemical shieldings]] and [[Calculating the magnetic susceptibility\|calculating the magnetic susceptibility]].		Follow these guides for [[Calculating the chemical shieldings\|calculating the chemical shieldings]] and [[Calculating the magnetic susceptibility\|calculating the magnetic susceptibility]].

Csheldon at 11:54, 12 May 2025

2025-05-12T11:54:01Z

← Older revision		Revision as of 11:54, 12 May 2025
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	{{NB\|warning\|This method only works for non-metallic systems, i.e., that have a finite bandgap.}}		{{NB\|warning\|This method only works for non-metallic systems, i.e., that have a finite bandgap.}}

	~~A guide~~ for ~~calculating the chemical shieldings can be found~~ [[Calculating the chemical shieldings\|~~here~~]] and ~~the magnetic susceptibility~~ [[Calculating the magnetic susceptibility\|~~here~~]].		Follow these guides for [[Calculating the chemical shieldings\|calculating the chemical shieldings]] and [[Calculating the magnetic susceptibility\|calculating the magnetic susceptibility]].

	== Definitions ==		== Definitions ==

Csheldon: /* Related tags and articles */

2025-03-25T11:29:15Z

Csheldon at 11:26, 25 March 2025

2025-03-25T11:26:46Z

← Older revision		Revision as of 11:26, 25 March 2025
Line 7:		Line 7:
	See also {{TAG\|WRT_NMRCUR}} to write the currents and {{TAG\|NUCIND}} to compute the nucleus-independent chemical shielding (NICS).		See also {{TAG\|WRT_NMRCUR}} to write the currents and {{TAG\|NUCIND}} to compute the nucleus-independent chemical shielding (NICS).
	{{NB\|warning\|This method only works for non-metallic systems, i.e., that have a finite bandgap.}}		{{NB\|warning\|This method only works for non-metallic systems, i.e., that have a finite bandgap.}}

			A guide for calculating the chemical shieldings can be found [[Calculating the chemical shieldings\|here]] and the magnetic susceptibility [[Calculating the magnetic susceptibility\|here]].

	== Definitions ==		== Definitions ==

Csheldon: /* Related tags and articles */

2025-03-21T14:34:07Z

← Older revision		Revision as of 15:33, 26 May 2025
Line 4:		Line 4:
	----		----
	For {{TAGO\|LCHIMAG\|True}}, the chemical shift tensors and magnetic susceptibility is computed. The implementation{{Cite\|dewijs:laskowski:jcp:2017}} is based on linear response theory using the gauge-invariant PAW method of Yates, Pickard, and Mauri {{Cite\|pickard:prb:2001}}{{Cite\|yates:prb:2007}}, that is an extension to the standard [[PAW method]] to account for the effects of a vector gauge field <math>A</math>. The NMR response currents are computed and the induced B field is calculated based on the Biot-Savart law.		For {{TAGO\|LCHIMAG\|True}}, the chemical shift tensors and magnetic susceptibility is computed. The implementation{{Cite\|dewijs:laskowski:jcp:2017}} is based on linear response theory using the gauge-invariant PAW method of Yates, Pickard, and Mauri {{Cite\|pickard:prb:2001}}{{Cite\|yates:prb:2007}}, that is an extension to the standard [[PAW method]] to account for the effects of a vector gauge field <math>A</math>. The NMR response currents are computed and the induced B field is calculated based on the Biot-Savart law.
			<!--
	See also {{TAG\|WRT_NMRCUR}} to write the currents and {{TAG\|NUCIND}} to compute the nucleus-independent chemical shielding (NICS).		See also {{TAG\|WRT_NMRCUR}} to write the currents and {{TAG\|NUCIND}} to compute the nucleus-independent chemical shielding (NICS).
	{{NB\|warning\|This method only works for non-metallic systems, i.e., that have a finite bandgap.}}		{{NB\|warning\|This method only works for non-metallic systems, i.e., that have a finite bandgap.}}-->

	Follow these guides for [[Calculating the chemical shieldings\|calculating the chemical shieldings]] and [[Calculating the magnetic susceptibility\|calculating the magnetic susceptibility]].		Follow these guides for [[Calculating the chemical shieldings\|calculating the chemical shieldings]] and [[Calculating the magnetic susceptibility\|calculating the magnetic susceptibility]].

← Older revision		Revision as of 11:29, 25 March 2025
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	{{TAG\|LVGVAPPL}},		{{TAG\|LVGVAPPL}},
	{{TAG\|NUCIND}}		{{TAG\|NUCIND}}

			[[Calculating the chemical shieldings]], [[Calculating the magnetic susceptibility]]

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

← Older revision		Revision as of 14:34, 21 March 2025
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	{{TAG\|LBONE}},		{{TAG\|LBONE}},
	{{TAG\|LVGVCALC}},		{{TAG\|LVGVCALC}},
	{{TAG\|LVGVAPPL}}		{{TAG\|LVGVAPPL}},
			{{TAG\|NUCIND}}

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