Computing the work function - Revision history

Schlipf: /* Related tags and articles */

2024-06-12T08:53:18Z

Svijay at 13:41, 7 February 2024

2024-02-07T13:41:56Z

← Older revision		Revision as of 13:41, 7 February 2024
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	we suggest switching on the dipole correction by using the following INCAR tags: {{TAG\|LDIPOL}}, {{TAG\|IDIPOL}}, {{TAG\|DIPOL}}.		we suggest switching on the dipole correction by using the following INCAR tags: {{TAG\|LDIPOL}}, {{TAG\|IDIPOL}}, {{TAG\|DIPOL}}.
	The use of the dipole correction is crucial to obtaining a flat field-free region in the potential (''c.f''. next point).		The use of the dipole correction is crucial to obtaining a flat field-free region in the potential (''c.f''. next point).
	In addition to these tags, set the {{TAG\|LVHAR}}=T to output only the ~~hartree~~ and ionic potentials to the {{FILE\|LOCPOT}} file or set <code>{{TAGBL\|WRT_POTENTIAL}}=hartree ionic</code> to store the potentials in the {{FILE\|vaspout.h5}} file.		In addition to these tags, set the {{TAG\|LVHAR}}=T to output only the Hartree and ionic potentials to the {{FILE\|LOCPOT}} file or set <code>{{TAGBL\|WRT_POTENTIAL}}=hartree ionic</code> to store the potentials in the {{FILE\|vaspout.h5}} file.
	{{NB\|tip\| We recommend using only the Hartree and ionic potentials as the exchange-correlation potential decays very slowly in the vacuum region. Using the sum of the ~~hartree~~ and ionic potentials allows for determining the work function with significantly less vacuum requirements (and hence lower computational cost).}}		{{NB\|tip\| We recommend using only the Hartree and ionic potentials as the exchange-correlation potential decays very slowly in the vacuum region. Using the sum of the Hartree and ionic potentials allows for determining the work function with significantly less vacuum requirements (and hence lower computational cost).}}
	'''Step 3''': Compute the vacuum potential.		'''Step 3''': Compute the vacuum potential.
	Average the contents of the {{FILE\|LOCPOT}} or the /results/potential/hartree and /results/potential/ionic datasets of the {{FILE\|vaspout.h5}} file along the lattice vectors of the surface, (i.e., both directions perpendicular to the surface normal).		Average the contents of the {{FILE\|LOCPOT}} or the /results/potential/hartree and /results/potential/ionic datasets of the {{FILE\|vaspout.h5}} file along the lattice vectors of the surface, (i.e., both directions perpendicular to the surface normal).

Huebsch at 09:49, 7 February 2024

2024-02-07T09:49:02Z

← Older revision		Revision as of 09:49, 7 February 2024
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	we suggest switching on the dipole correction by using the following INCAR tags: {{TAG\|LDIPOL}}, {{TAG\|IDIPOL}}, {{TAG\|DIPOL}}.		we suggest switching on the dipole correction by using the following INCAR tags: {{TAG\|LDIPOL}}, {{TAG\|IDIPOL}}, {{TAG\|DIPOL}}.
	The use of the dipole correction is crucial to obtaining a flat field-free region in the potential (''c.f''. next point).		The use of the dipole correction is crucial to obtaining a flat field-free region in the potential (''c.f''. next point).
	In addition to these tags, set the {{TAG\|LVHAR}}=T to output only the hartree and ionic potentials to the {{FILE\|LOCPOT}} file or set {{~~TAG~~\|WRT_POTENTIAL}}=hartree, ionic to store the potentials in the {{FILE\|vaspout.h5}} file.		In addition to these tags, set the {{TAG\|LVHAR}}=T to output only the hartree and ionic potentials to the {{FILE\|LOCPOT}} file or set <code>{{TAGBL\|WRT_POTENTIAL}}=hartree ionic</code> to store the potentials in the {{FILE\|vaspout.h5}} file.
	{{NB\|tip\| We recommend using only the Hartree and ionic potentials as the exchange-correlation potential decays very slowly in the vacuum region. Using the sum of the hartree and ionic potentials allows for determining the work function with significantly less vacuum requirements (and hence lower computational cost).}}		{{NB\|tip\| We recommend using only the Hartree and ionic potentials as the exchange-correlation potential decays very slowly in the vacuum region. Using the sum of the hartree and ionic potentials allows for determining the work function with significantly less vacuum requirements (and hence lower computational cost).}}
	'''Step 3''': Compute the vacuum potential.		'''Step 3''': Compute the vacuum potential.

Svijay: /* Step-by-step instructions */

2024-02-07T08:14:53Z

Step-by-step instructions

← Older revision		Revision as of 08:14, 7 February 2024
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	we suggest switching on the dipole correction by using the following INCAR tags: {{TAG\|LDIPOL}}, {{TAG\|IDIPOL}}, {{TAG\|DIPOL}}.		we suggest switching on the dipole correction by using the following INCAR tags: {{TAG\|LDIPOL}}, {{TAG\|IDIPOL}}, {{TAG\|DIPOL}}.
	The use of the dipole correction is crucial to obtaining a flat field-free region in the potential (''c.f''. next point).		The use of the dipole correction is crucial to obtaining a flat field-free region in the potential (''c.f''. next point).
	In addition to these tags, set the {{TAG\|LVHAR}}=T to output only the ~~Hartree~~ and ionic potentials to the {{FILE\|LOCPOT}} file.		In addition to these tags, set the {{TAG\|LVHAR}}=T to output only the hartree and ionic potentials to the {{FILE\|LOCPOT}} file or set {{TAG\|WRT_POTENTIAL}}=hartree, ionic to store the potentials in the {{FILE\|vaspout.h5}} file.
	{{NB\|tip\| We recommend using only the Hartree and ionic potentials as the exchange-correlation potential decays very slowly in the vacuum region. Using the sum of the ~~Hartree~~ and ionic potentials allows for determining the work function with significantly less vacuum requirements (and hence lower computational cost).}}		{{NB\|tip\| We recommend using only the Hartree and ionic potentials as the exchange-correlation potential decays very slowly in the vacuum region. Using the sum of the hartree and ionic potentials allows for determining the work function with significantly less vacuum requirements (and hence lower computational cost).}}
	'''Step 3''': Compute the vacuum potential.		'''Step 3''': Compute the vacuum potential.
	Average the contents of the {{FILE\|LOCPOT}} file along the lattice vectors of the surface, (i.e., both directions perpendicular to the surface normal).		Average the contents of the {{FILE\|LOCPOT}} or the /results/potential/hartree and /results/potential/ionic datasets of the {{FILE\|vaspout.h5}} file along the lattice vectors of the surface, (i.e., both directions perpendicular to the surface normal).
	Find the field-free region by determining the region of space where the potential remains constant.		Find the field-free region by determining the region of space where the potential remains constant.
	This value of the potential is the vacuum potential.		This value of the potential is the vacuum potential.

Huebsch: /* Related tags and articles */

2024-02-06T14:20:07Z

Svijay at 09:59, 5 February 2024

2024-02-05T09:59:26Z

← Older revision		Revision as of 09:59, 5 February 2024
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	This value of the potential is the vacuum potential.		This value of the potential is the vacuum potential.
	{{NB\|tip\| There exist two vacuum potential regions, one for either direction of the surface normal. Depending on your system, one of the directions may be more relevant than another.}}		{{NB\|tip\| There exist two vacuum potential regions, one for either direction of the surface normal. Depending on your system, one of the directions may be more relevant than another.}}
	'''Step 3b''': Alternatively, VASP can compute the vacuum potential when you set {{TAG\|~~VACPOTAV~~}}=T in the INCAR file.		'''Step 3b''': Alternatively, VASP can compute the vacuum potential when you set {{TAG\|LVACPOTAV}}=T in the INCAR file.
	You can then <code>grep</code> for the output in the {{FILE\|OUTCAR}} file		You can then <code>grep</code> for the output in the {{FILE\|OUTCAR}} file

Svijay: /* Step-by-step instructions */

2024-02-05T08:50:03Z

Step-by-step instructions

← Older revision		Revision as of 08:50, 5 February 2024
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	The use of the dipole correction is crucial to obtaining a flat field-free region in the potential (''c.f''. next point).		The use of the dipole correction is crucial to obtaining a flat field-free region in the potential (''c.f''. next point).
	In addition to these tags, set the {{TAG\|LVHAR}}=T to output only the Hartree and ionic potentials to the {{FILE\|LOCPOT}} file.		In addition to these tags, set the {{TAG\|LVHAR}}=T to output only the Hartree and ionic potentials to the {{FILE\|LOCPOT}} file.
	{{NB\|tip\| We recommend using only the Hartree and ionic potentials as the exchange-correlation potential decays very slowly in vacuum. Using the sum of the Hartree and ionic potentials allows for determining the work function with significantly less vacuum requirements (and hence lower computational cost).}}		{{NB\|tip\| We recommend using only the Hartree and ionic potentials as the exchange-correlation potential decays very slowly in the vacuum region. Using the sum of the Hartree and ionic potentials allows for determining the work function with significantly less vacuum requirements (and hence lower computational cost).}}
	'''Step 3''': Compute the vacuum potential.		'''Step 3''': Compute the vacuum potential.
	Average the contents of the {{FILE\|LOCPOT}} file along the lattice vectors of the surface, (i.e., both directions perpendicular to the surface normal).		Average the contents of the {{FILE\|LOCPOT}} file along the lattice vectors of the surface, (i.e., both directions perpendicular to the surface normal).

Svijay: /* Step-by-step instructions */ Introduce VACPOTAV

2024-02-05T07:36:46Z

Step-by-step instructions: Introduce VACPOTAV

← Older revision		Revision as of 07:36, 5 February 2024
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	This value of the potential is the vacuum potential.		This value of the potential is the vacuum potential.
	{{NB\|tip\| There exist two vacuum potential regions, one for either direction of the surface normal. Depending on your system, one of the directions may be more relevant than another.}}		{{NB\|tip\| There exist two vacuum potential regions, one for either direction of the surface normal. Depending on your system, one of the directions may be more relevant than another.}}
	~~<!---~~'''Step 3b''': Alternatively, VASP can compute the vacuum potential when you set {{TAG\|VACPOTAV}}=T in the INCAR file.		'''Step 3b''': Alternatively, VASP can compute the vacuum potential when you set {{TAG\|VACPOTAV}}=T in the INCAR file.
	You can then <code>grep</code> for the output in the {{FILE\|OUTCAR}} file		You can then <code>grep</code> for the output in the {{FILE\|OUTCAR}} file

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	vacuum level on the upper side and lower side of the slab 8.049 7.778		vacuum level on the upper side and lower side of the slab 8.049 7.778
	~~-->~~
	'''Step 4''': Determine the Fermi energy.		'''Step 4''': Determine the Fermi energy.
	The Fermi energy is written directly to the {{FILE\|OUTCAR}} file. <code>grep</code> for the following lines in the {{FILE\|OUTCAR}} to get the Fermi energy in eV.		The Fermi energy is written directly to the {{FILE\|OUTCAR}} file. <code>grep</code> for the following lines in the {{FILE\|OUTCAR}} to get the Fermi energy in eV.

Huebsch: /* Example */

2023-11-01T13:22:12Z

Example

← Older revision		Revision as of 13:22, 1 November 2023
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	An example {{FILE\|INCAR}} file for this system is,		An example {{FILE\|INCAR}} file for this system is,

	LDIPOL = T		{{TAGBL\|LDIPOL}} = T
	IDIPOL = 3		{{TAGBL\|IDIPOL}} = 3
	DIPOL = 0.5 0.5 0.5		{{TAGBL\|DIPOL}} = 0.5 0.5 0.5
	LVHAR = T		{{TAGBL\|LVHAR}} = T
	PREC = Accurate		{{TAGBL\|PREC}} = Accurate

	The Figure to the right shows a representative example of the vacuum potential obtained by averaging the contents of {{FILE\|LOCPOT}}.		The Figure to the right shows a representative example of the vacuum potential obtained by averaging the contents of {{FILE\|LOCPOT}}.
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	''fcc'' Pt(111) surface (in blue) and Pt(111) surface with a carbon atom adsorbed on one surface termination (Pt(111)-C*).		''fcc'' Pt(111) surface (in blue) and Pt(111) surface with a carbon atom adsorbed on one surface termination (Pt(111)-C*).
	The vacuum potentials are flat, (i.e., constant), on either side (magnified in insets).		The vacuum potentials are flat, (i.e., constant), on either side (magnified in insets).
	The work function on either side of the slab is annotated in the insets as <math display="inline">\Phi</math>. It is equal for both sides of the clean slab, but slightly higher for the case of Pt(111)-C*.		The work function on either side of the slab is annotated in the insets as <math display="inline">\Phi</math>. It is equal for both sides of the clean slab but slightly higher for the case of Pt(111)-C*.

	==Related tags and articles==		==Related tags and articles==
	{{FILE\|LOCPOT}}, {{TAG\|LDIPOL}}, {{TAG\|IDIPOL}}, {{TAG\|DIPOL}}		{{FILE\|LOCPOT}}, {{TAG\|LDIPOL}}, {{TAG\|IDIPOL}}, {{TAG\|DIPOL}}

	[[Category:Howto]][[Category:Electrostatics]]		[[Category:Howto]][[Category:Electrostatics]]

Huebsch: Huebsch moved page Computing the Workfunction to Computing the work function

2023-10-20T10:20:50Z

Huebsch moved page Computing the Workfunction to Computing the work function

← Older revision

Revision as of 10:20, 20 October 2023

← Older revision		Revision as of 08:53, 12 June 2024
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	{{FILE\|LOCPOT}}, {{TAG\|LDIPOL}}, {{TAG\|IDIPOL}}, {{TAG\|DIPOL}}, {{TAG\|LVHAR}}, {{TAG\|WRT_POTENTIAL}}		{{FILE\|LOCPOT}}, {{TAG\|LDIPOL}}, {{TAG\|IDIPOL}}, {{TAG\|DIPOL}}, {{TAG\|LVHAR}}, {{TAG\|WRT_POTENTIAL}}

	[[Category:Howto]][[Category:Electrostatics]]		[[Category:Howto]][[Category:Electrostatics]][[Category:Electronic ground-state properties]]

← Older revision		Revision as of 14:20, 6 February 2024
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	==Related tags and articles==		==Related tags and articles==
	{{FILE\|LOCPOT}}, {{TAG\|LDIPOL}}, {{TAG\|IDIPOL}}, {{TAG\|DIPOL}}		{{FILE\|LOCPOT}}, {{TAG\|LDIPOL}}, {{TAG\|IDIPOL}}, {{TAG\|DIPOL}}, {{TAG\|LVHAR}}, {{TAG\|WRT_POTENTIAL}}

	[[Category:Howto]][[Category:Electrostatics]]		[[Category:Howto]][[Category:Electrostatics]]