Category:Electronic occupancy - Revision history

Huebsch at 06:39, 20 October 2025

2025-10-20T06:39:44Z

← Older revision		Revision as of 06:39, 20 October 2025
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	Within the [[PAW method]] there is the occupation <math>f_k</math> for the plane-wave part and the on-site occupation matrix <math>\rho</math> that characterize the [[Electronic ground-state properties\|electronic state]]. Below we list tags and sections that can be used to influence the occupation, besides the obvious influence of the specific [[Ionic minimization\|structure]] and [[XC functional\|exchange-correlation effects]].		Within the [[PAW method]] there is the occupation <math>f_k</math> for the plane-wave part and the on-site occupation matrix <math>\rho</math> that characterize the [[Electronic ground-state properties\|electronic state]]. Below we list tags and sections that can be used to influence the occupation, besides the obvious influence of the specific [[Ionic minimization\|structure]] and [[XC functional\|exchange-correlation effects]].

	== ~~Theory~~ ==		== Modeling excited states by constrained occupation calculations ==

	~~=== Density Functional Theory plus Dynamical Mean Field Theory ===~~		The '''delta self-consistent field (ΔSCF)''' method provides a practical way to obtain neutral excitation energies within density functional theory (DFT) by explicitly constraining the electronic '''occupations''' of selected orbitals.
			In contrast to [[:Category:Linear_response\|linear-response]] or [[:Category:Many-body perturbation theory\|many-body approaches]], ΔSCF directly evaluates the total energy difference between ground and excited electronic configurations from self-consistent calculations.
			This approach connects closely to experimental observables such as the '''vertical absorption energy (VAE)''', '''vertical emission energy (VEE)''', and '''zero-phonon lines (ZPLs)''', which are key quantities in the [[:Category:Dielectric properties\|optical spectroscopy]] of point defects in semiconductors and insulators {{cite\|Freysoldt2014}}.

	Density Functional Theory plus Dynamical Mean Field Theory (DFT+DMFT){{cite\|kotliar:rmp:2006}} is an advanced extension of DFT that provides a more accurate treatment of strongly correlated materials compared to [[~~:Category:DFT+U~~\|~~DFT+U~~]]. While DFT+U incorporates a static correction for localized electron interactions, DFT+DMFT goes further by treating these interactions dynamically, capturing frequency-dependent electron correlations. A key feature of DFT+DMFT is that the charge density is updated using the DMFT solution, ensuring a self-consistent feedback between the correlated electronic states and the DFT potential. This not only improves the description of ~~phenomena like metal~~-~~insulator transitions and quasiparticle renormalization but also allows for the~~ calculation of spectral properties such as photoemission spectra, transport properties, and total energies relevant to structural distortions. To facilitate DFT+DMFT calculations, VASP provides a general interface to DMFT codes, allowing occupation updates {{TAG\|ICHARG}}=~~5 via an external file~~ {~~{FILE\|vaspgamma.h5}~~} / ~~{{FILE\|GAMMA}} to update the charge density.~~		*[[Delta self-consistent field\|<math display="inline">\Delta\mathrm{SCF}</math> calculations]]: example of zero-phonon line calculation of <math display="inline">\mathrm{NV}^-</math> center in diamond

	== ~~How to~~ ==		== Density-functional theory plus dynamical mean-field theory ==
	~~Practical guides~~ to ~~different methods manipulating occupations in~~ VASP ~~are found on following pages:~~
			'''Density-functional theory plus dynamical mean-field theory (DFT+DMFT)'''{{cite\|kotliar:rmp:2006}} is a method that provides a more accurate treatment of '''strongly correlated materials''' compared to [[:Category:DFT+U\|DFT+U]]. While [[:Category:DFT+U\|DFT+U]] is computationally much more affordable, it incorporates a static correction for localized electron interactions. DFT+DMFT, on the other hand, goes further by treating these interactions dynamically, capturing frequency-dependent electron correlations. A key feature of DFT+DMFT is that the charge density is updated using the DMFT solution, ensuring a self-consistent feedback between the correlated electronic states and the DFT potential. This not only improves the description of phenomena like '''metal-insulator transitions''' and quasiparticle renormalization but also allows for the calculation of spectral properties such as '''photoemission spectra''', '''transport properties''', and '''total energies relevant to structural distortions'''. To facilitate DFT+DMFT calculations, VASP provides a general interface to DMFT codes, allowing occupation updates {{TAG\|ICHARG}}=5 via an external file {{FILE\|vaspgamma.h5}} / {{FILE\|GAMMA}} to update the charge density.

	*{{TAG\|DFT+DMFT calculations}}: example of performing DFT+DMFT calculations using the [https://triqs.github.io/triqs TRIQS software]{{cite\|parcollet:cpc:196}}		*{{TAG\|DFT+DMFT calculations}}: example of performing DFT+DMFT calculations using the [https://triqs.github.io/triqs TRIQS software]{{cite\|parcollet:cpc:196}}
	*[[Delta Self-Consistent Field\|<math display="inline">\Delta\mathrm{SCF}</math> calculations]]: example of zero-phonon line calculation of <math display="inline">\mathrm{NV}^-</math> center in diamond

	== References ==		== References ==

Tal: /* How to */

2025-10-16T15:56:25Z

How to

← Older revision		Revision as of 15:56, 16 October 2025
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	*{{TAG\|DFT+DMFT calculations}}: example of performing DFT+DMFT calculations using the [https://triqs.github.io/triqs TRIQS software]{{cite\|parcollet:cpc:196}}		*{{TAG\|DFT+DMFT calculations}}: example of performing DFT+DMFT calculations using the [https://triqs.github.io/triqs TRIQS software]{{cite\|parcollet:cpc:196}}
	*[[~~Construction:Deltascf~~\|<math display="inline">\Delta\mathrm{SCF}</math> calculations]]: example of zero-phonon line calculation of <math display="inline">\mathrm{NV}^-</math> center in diamond		*[[Delta Self-Consistent Field\|<math display="inline">\Delta\mathrm{SCF}</math> calculations]]: example of zero-phonon line calculation of <math display="inline">\mathrm{NV}^-</math> center in diamond

	== References ==		== References ==

Tal: /* How to */

2025-10-16T15:30:23Z

How to

← Older revision		Revision as of 15:30, 16 October 2025
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	*{{TAG\|DFT+DMFT calculations}}: example of performing DFT+DMFT calculations using the [https://triqs.github.io/triqs TRIQS software]{{cite\|parcollet:cpc:196}}		*{{TAG\|DFT+DMFT calculations}}: example of performing DFT+DMFT calculations using the [https://triqs.github.io/triqs TRIQS software]{{cite\|parcollet:cpc:196}}
	*[[Construction:Deltascf\|<math display="inline">\Delta\mathrm{SCF}</math> calculations]]: example of zero-phonon line calculation of <math display="inline">\mathrm{NV}^-</math> center in diamond.		*[[Construction:Deltascf\|<math display="inline">\Delta\mathrm{SCF}</math> calculations]]: example of zero-phonon line calculation of <math display="inline">\mathrm{NV}^-</math> center in diamond

	== References ==		== References ==

Tal: /* How to */

2025-10-16T15:30:15Z

How to

← Older revision		Revision as of 15:30, 16 October 2025
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	*{{TAG\|DFT+DMFT calculations}}: example of performing DFT+DMFT calculations using the [https://triqs.github.io/triqs TRIQS software]{{cite\|parcollet:cpc:196}}		*{{TAG\|DFT+DMFT calculations}}: example of performing DFT+DMFT calculations using the [https://triqs.github.io/triqs TRIQS software]{{cite\|parcollet:cpc:196}}
			*[[Construction:Deltascf\|<math display="inline">\Delta\mathrm{SCF}</math> calculations]]: example of zero-phonon line calculation of <math display="inline">\mathrm{NV}^-</math> center in diamond.

	== References ==		== References ==

Ftran at 15:51, 27 February 2025

2025-02-27T15:51:54Z

← Older revision		Revision as of 15:51, 27 February 2025
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	=== Density Functional Theory plus Dynamical Mean Field Theory ===		=== Density Functional Theory plus Dynamical Mean Field Theory ===

	Density Functional Theory plus Dynamical Mean Field Theory (DFT+DMFT){{cite\|kotliar:rmp:2006}} is an advanced extension of DFT that provides a more accurate treatment of strongly correlated materials compared to ~~the {{TAG~~\|DFT+U~~: formalism}}~~. While DFT+U incorporates a static correction for localized electron interactions, DFT+DMFT goes further by treating these interactions dynamically, capturing frequency-dependent electron correlations. A key feature of DFT+DMFT is that the charge density is updated using the DMFT solution, ensuring a self-consistent feedback between the correlated electronic states and the DFT potential. This not only improves the description of phenomena like metal-insulator transitions and quasiparticle renormalization but also allows for the calculation of spectral properties such as photoemission spectra, transport properties, and total energies relevant to structural distortions. To facilitate DFT+DMFT calculations, VASP provides a general interface to DMFT codes, allowing occupation updates {{TAG\|ICHARG}}=5 via an external file {{FILE\|vaspgamma.h5}} / {{FILE\|GAMMA}} to update the charge density.		Density Functional Theory plus Dynamical Mean Field Theory (DFT+DMFT){{cite\|kotliar:rmp:2006}} is an advanced extension of DFT that provides a more accurate treatment of strongly correlated materials compared to [[:Category:DFT+U\|DFT+U]]. While DFT+U incorporates a static correction for localized electron interactions, DFT+DMFT goes further by treating these interactions dynamically, capturing frequency-dependent electron correlations. A key feature of DFT+DMFT is that the charge density is updated using the DMFT solution, ensuring a self-consistent feedback between the correlated electronic states and the DFT potential. This not only improves the description of phenomena like metal-insulator transitions and quasiparticle renormalization but also allows for the calculation of spectral properties such as photoemission spectra, transport properties, and total energies relevant to structural distortions. To facilitate DFT+DMFT calculations, VASP provides a general interface to DMFT codes, allowing occupation updates {{TAG\|ICHARG}}=5 via an external file {{FILE\|vaspgamma.h5}} / {{FILE\|GAMMA}} to update the charge density.

	== How to ==		== How to ==

Hampel at 16:48, 20 February 2025

2025-02-20T16:48:09Z

← Older revision		Revision as of 16:48, 20 February 2025
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	Practical guides to different methods manipulating occupations in VASP are found on following pages:		Practical guides to different methods manipulating occupations in VASP are found on following pages:

	*{{TAG\|DFT+DMFT calculations}}: example of performing DFT+DMFT calculations using the TRIQS software{{cite\|parcollet:cpc:196}}		*{{TAG\|DFT+DMFT calculations}}: example of performing DFT+DMFT calculations using the [https://triqs.github.io/triqs TRIQS software]{{cite\|parcollet:cpc:196}}

	== References ==		== References ==

Hampel at 10:08, 20 February 2025

2025-02-20T10:08:26Z

← Older revision		Revision as of 10:08, 20 February 2025
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	Within the [[PAW method]] there is the occupation <math>f_k</math> for the plane-wave part and the on-site occupation matrix <math>\rho</math> that characterize the [[Electronic ground-state properties\|electronic state]]. Below we list tags and sections that can be used to influence the occupation, besides the obvious influence of the specific [[Ionic minimization\|structure]] and [[XC functional\|exchange-correlation effects]].		Within the [[PAW method]] there is the occupation <math>f_k</math> for the plane-wave part and the on-site occupation matrix <math>\rho</math> that characterize the [[Electronic ground-state properties\|electronic state]]. Below we list tags and sections that can be used to influence the occupation, besides the obvious influence of the specific [[Ionic minimization\|structure]] and [[XC functional\|exchange-correlation effects]].

			== Theory ==

			=== Density Functional Theory plus Dynamical Mean Field Theory ===

			Density Functional Theory plus Dynamical Mean Field Theory (DFT+DMFT){{cite\|kotliar:rmp:2006}} is an advanced extension of DFT that provides a more accurate treatment of strongly correlated materials compared to the {{TAG\|DFT+U: formalism}}. While DFT+U incorporates a static correction for localized electron interactions, DFT+DMFT goes further by treating these interactions dynamically, capturing frequency-dependent electron correlations. A key feature of DFT+DMFT is that the charge density is updated using the DMFT solution, ensuring a self-consistent feedback between the correlated electronic states and the DFT potential. This not only improves the description of phenomena like metal-insulator transitions and quasiparticle renormalization but also allows for the calculation of spectral properties such as photoemission spectra, transport properties, and total energies relevant to structural distortions. To facilitate DFT+DMFT calculations, VASP provides a general interface to DMFT codes, allowing occupation updates {{TAG\|ICHARG}}=5 via an external file {{FILE\|vaspgamma.h5}} / {{FILE\|GAMMA}} to update the charge density.

			== How to ==
			Practical guides to different methods manipulating occupations in VASP are found on following pages:

			*{{TAG\|DFT+DMFT calculations}}: example of performing DFT+DMFT calculations using the TRIQS software{{cite\|parcollet:cpc:196}}

			== References ==
			<references/>
			----

	[[Category:Electronic ground-state properties]][[Category:Electronic minimization]]		[[Category:Electronic ground-state properties]][[Category:Electronic minimization]]

Huebsch at 10:13, 17 October 2024

2024-10-17T10:13:39Z

← Older revision		Revision as of 10:13, 17 October 2024
Line 1:		Line 1:
	Within the [[PAW method]] there is the occupation <math>f_k</math> for the plane-wave part and the on-site occupation matrix <math>\rho</math> that characterize the [[Electronic ground-state properties\|electronic state]]. Below we list tags and sections that can be used to influence the occupation, besides the obvious influence of the specific [[Ionic minimization\|structure]] and [[XC functional\|exchange-correlation effects]].		Within the [[PAW method]] there is the occupation <math>f_k</math> for the plane-wave part and the on-site occupation matrix <math>\rho</math> that characterize the [[Electronic ground-state properties\|electronic state]]. Below we list tags and sections that can be used to influence the occupation, besides the obvious influence of the specific [[Ionic minimization\|structure]] and [[XC functional\|exchange-correlation effects]].

	[[Category:Electronic ground-state ~~property~~]][[Category:Electronic minimization]]		[[Category:Electronic ground-state properties]][[Category:Electronic minimization]]

Huebsch at 10:13, 17 October 2024

2024-10-17T10:13:29Z

← Older revision		Revision as of 10:13, 17 October 2024
Line 1:		Line 1:
	Within the [[PAW method]] there is the occupation <math>f_k</math> for the plane-wave part and the on-site occupation matrix <math>\rho</math> that characterize the [[Electronic ground-state properties\|electronic state]]. Below we list tags and sections that can be used to influence the occupation, besides the obvious influence of the specific [[Ionic minimization\|structure]] and [[XC functional\|exchange-correlation effects]].		Within the [[PAW method]] there is the occupation <math>f_k</math> for the plane-wave part and the on-site occupation matrix <math>\rho</math> that characterize the [[Electronic ground-state properties\|electronic state]]. Below we list tags and sections that can be used to influence the occupation, besides the obvious influence of the specific [[Ionic minimization\|structure]] and [[XC functional\|exchange-correlation effects]].

			[[Category:Electronic ground-state property]][[Category:Electronic minimization]]

Huebsch: Huebsch moved page Electronic occupancy to Category:Electronic occupancy

2024-10-17T10:09:14Z

Huebsch moved page Electronic occupancy to Category:Electronic occupancy

← Older revision	Revision as of 10:09, 17 October 2024
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