LiF - Revision history

Attacc: /* ALDA (yambo -o c -k alda) */

2025-06-08T09:20:05Z

ALDA (yambo -o c -k alda)

← Older revision		Revision as of 09:20, 8 June 2025
Line 161:		Line 161:

	Our first attempt to go beyond RPA is using TDDFT in the Adiabatic LDA approximation. Depending on the exchange-correlation(xc) functional used in the ground state calculation yambo will produce a corresponding xc-kernel. In this case, as reported by the ''a2y'' command we are using a Perdew Wang parametrization.		Our first attempt to go beyond RPA is using TDDFT in the Adiabatic LDA approximation. Depending on the exchange-correlation(xc) functional used in the ground state calculation yambo will produce a corresponding xc-kernel. In this case, as reported by the ''a2y'' command we are using a Perdew Wang parametrization.

	~~optics # [R] Linear Response optical properties~~
	~~chi # [R][CHI] Dyson equation for Chi.~~
	~~% QpntsRXd~~
	~~<span style="color:red"> 1 \| 1 \| </span> # [Xd] Transferred momenta~~
	%
	~~% BndsRnXd~~
	~~<span style="color:red"> 1 \| 10 \| </span> # [Xd] Polarization function bands~~
	%
	~~% EnRngeXd~~
	~~<span style="color:red"> 7.50000 \| 25.00000 \| </span> eV # [Xd] Energy range~~
	%
	~~% DmRngeXd~~
	~~0.100000 \| 0.100000 \| eV # [Xd] Damping range~~
	%
	~~ETStpsXd= <span style="color:red">300 </span> # [Xd] Total Energy steps~~
	~~% LongDrXd~~
	~~1.000000 \| 0.000000 \| 0.000000 \| # [Xd] [cc] Electric Field~~
	%

	Generate input file with the command: <code> yambo -o c -k alda -F tdlda.in</code>		Generate input file with the command: <code> yambo -o c -k alda -F tdlda.in</code>

Attacc: /* ALDA (yambo -o c -k alda) */

2025-06-08T09:19:44Z

ALDA (yambo -o c -k alda)

← Older revision		Revision as of 09:19, 8 June 2025
Line 161:		Line 161:

	Our first attempt to go beyond RPA is using TDDFT in the Adiabatic LDA approximation. Depending on the exchange-correlation(xc) functional used in the ground state calculation yambo will produce a corresponding xc-kernel. In this case, as reported by the ''a2y'' command we are using a Perdew Wang parametrization.		Our first attempt to go beyond RPA is using TDDFT in the Adiabatic LDA approximation. Depending on the exchange-correlation(xc) functional used in the ground state calculation yambo will produce a corresponding xc-kernel. In this case, as reported by the ''a2y'' command we are using a Perdew Wang parametrization.

			optics # [R] Linear Response optical properties
			chi # [R][CHI] Dyson equation for Chi.
			% QpntsRXd
			<span style="color:red"> 1 \| 1 \| </span> # [Xd] Transferred momenta
			%
			% BndsRnXd
			<span style="color:red"> 1 \| 10 \| </span> # [Xd] Polarization function bands
			%
			% EnRngeXd
			<span style="color:red"> 7.50000 \| 25.00000 \| </span> eV # [Xd] Energy range
			%
			% DmRngeXd
			0.100000 \| 0.100000 \| eV # [Xd] Damping range
			%
			ETStpsXd= <span style="color:red">300 </span> # [Xd] Total Energy steps
			% LongDrXd
			1.000000 \| 0.000000 \| 0.000000 \| # [Xd] [cc] Electric Field
			%

	Generate input file with the command: <code> yambo -o c -k alda -F tdlda.in</code>		Generate input file with the command: <code> yambo -o c -k alda -F tdlda.in</code>

Attacc: /* ALDA (yambo -o c -k alda) */

2025-03-31T14:14:11Z

ALDA (yambo -o c -k alda)

← Older revision		Revision as of 14:14, 31 March 2025
Line 191:		Line 191:
	used for the exchange correlation functional (FxcGRLc).		used for the exchange correlation functional (FxcGRLc).
	You can run the input with the command: <code>yambo -F tdlda.in</code>		You can run the input with the command: <code>yambo -F tdlda.in</code>

			Output will be in the file <code>o.eps_q1_inv_alda_dyson</code>, where the first column is the energy while the second and third are the imaginary
			and real parts of the dielectric constant.

	[[File:LiF_04.png\|512x384px]]		[[File:LiF_04.png\|512x384px]]

Attacc: /* ALDA (yambo -o c -k alda) */

2025-03-31T14:13:01Z

ALDA (yambo -o c -k alda)

← Older revision		Revision as of 14:13, 31 March 2025
Line 162:		Line 162:
	Our first attempt to go beyond RPA is using TDDFT in the Adiabatic LDA approximation. Depending on the exchange-correlation(xc) functional used in the ground state calculation yambo will produce a corresponding xc-kernel. In this case, as reported by the ''a2y'' command we are using a Perdew Wang parametrization.		Our first attempt to go beyond RPA is using TDDFT in the Adiabatic LDA approximation. Depending on the exchange-correlation(xc) functional used in the ground state calculation yambo will produce a corresponding xc-kernel. In this case, as reported by the ''a2y'' command we are using a Perdew Wang parametrization.

	Generate input file with the command: <code> yambo -o c -k alda</code>		Generate input file with the command: <code> yambo -o c -k alda -F tdlda.in</code>

	optics # [R] Linear Response optical properties		optics # [R] Linear Response optical properties
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	In this input we set to 51 RL (reciprocal lattice vectors) the size of the dielectric constant. This is also the number of RL vectors		In this input we set to 51 RL (reciprocal lattice vectors) the size of the dielectric constant. This is also the number of RL vectors
	used for the exchange correlation functional (FxcGRLc).		used for the exchange correlation functional (FxcGRLc).
			You can run the input with the command: <code>yambo -F tdlda.in</code>

	[[File:LiF_04.png\|512x384px]]		[[File:LiF_04.png\|512x384px]]

Attacc: /* ALDA (yambo -o c -k alda) */

2025-03-31T14:12:15Z

ALDA (yambo -o c -k alda)

← Older revision		Revision as of 14:12, 31 March 2025
Line 188:		Line 188:
	%		%

			In this input we set to 51 RL (reciprocal lattice vectors) the size of the dielectric constant. This is also the number of RL vectors
			used for the exchange correlation functional (FxcGRLc).

	[[File:LiF_04.png\|512x384px]]		[[File:LiF_04.png\|512x384px]]

Attacc: /* ALDA (yambo -o c -k alda) */

2025-03-31T14:11:12Z

ALDA (yambo -o c -k alda)

← Older revision		Revision as of 14:11, 31 March 2025
Line 175:		Line 175:
	%		%
	% BndsRnXd		% BndsRnXd
	<span style="color:red"> 1 \| 10 \| </span< # [Xd] Polarization function bands		<span style="color:red"> 1 \| 10 \| </span> # [Xd] Polarization function bands
	%		%
	% EnRngeXd		% EnRngeXd

Attacc: /* ALDA (yambo -o c -k alda) */

2025-03-31T14:11:04Z

ALDA (yambo -o c -k alda)

← Older revision		Revision as of 14:11, 31 March 2025
Line 175:		Line 175:
	%		%
	% BndsRnXd		% BndsRnXd
	<span style="color:red"> 1 \| 10 \| </span< # [Xd] Polarization function bands		<span style="color:red"> 1 \| 10 \| </span< # [Xd] Polarization function bands
	%		%
	% EnRngeXd		% EnRngeXd

Attacc: /* ALDA (yambo -o c -k alda) */

2025-03-31T14:10:53Z

ALDA (yambo -o c -k alda)

← Older revision		Revision as of 14:10, 31 March 2025
Line 169:		Line 169:
	#DegFix # Force the code to impose the energy levels to respect their degeneracy		#DegFix # Force the code to impose the energy levels to respect their degeneracy
	Chimod= "ALDA" # [X] IP/Hartree/ALDA/LRC/PF/BSfxc		Chimod= "ALDA" # [X] IP/Hartree/ALDA/LRC/PF/BSfxc
	FxcGRLc= 51 RL # [TDDFT] XC-kernel RL size		FxcGRLc= <span style="color:red">51 </span> RL # [TDDFT] XC-kernel RL size
	NGsBlkXd= 51 RL # [Xd] Response block size		NGsBlkXd= <span style="color:red">51 </span> RL # [Xd] Response block size
	% QpntsRXd		% QpntsRXd
	1 \| 1 \| # [Xd] Transferred momenta		<span style="color:red"> 1 \| 1 \| </span> # [Xd] Transferred momenta
	%		%
	% BndsRnXd		% BndsRnXd
	1 \| 10 \| # [Xd] Polarization function bands		<span style="color:red"> 1 \| 10 \| </span< # [Xd] Polarization function bands
	%		%
	% EnRngeXd		% EnRngeXd
	7.50000 \| 25.00000 \| eV # [Xd] Energy range		<span style="color:red"> 7.50000 \| 25.00000 \| </span> eV # [Xd] Energy range
	%		%
	% DmRngeXd		% DmRngeXd
	0.100000 \| 0.~~300000~~ \| eV # [Xd] Damping range		0.100000 \| 0.100000 \| eV # [Xd] Damping range
	%		%
	ETStpsXd= 300 # [Xd] Total Energy steps		ETStpsXd= <span style="color:red">300 </span> # [Xd] Total Energy steps
	% LongDrXd		% LongDrXd
	1.000000 \| 0.000000 \| 0.000000 \| # [Xd] [cc] Electric Field		1.000000 \| 0.000000 \| 0.000000 \| # [Xd] [cc] Electric Field

Attacc: /* ALDA (yambo -o c -k alda) */

2025-03-31T14:09:53Z

ALDA (yambo -o c -k alda)

@@ Line 162: / Line 162: @@
 Our first attempt to go beyond RPA is using TDDFT in the Adiabatic LDA approximation. Depending on the exchange-correlation(xc) functional used in the ground state calculation yambo will produce a corresponding xc-kernel. In this case, as reported by the ''a2y'' command we are using a Perdew Wang parametrization.
-Running
+Generate input file with the command: <code> yambo -o c -k alda</code>
 [[File:LiF_04.png|512x384px]]
@@ Line 172: / Line 195: @@
 <span id="05"></span>
 =The Statically screened Electron-electron interaction (yambo -X s) =

Attacc: /* A Bethe-Salpeter based Fxc(yambo -o c -k lrc) */

2025-02-14T09:02:06Z

A Bethe-Salpeter based Fxc(yambo -o c -k lrc)

← Older revision		Revision as of 09:02, 14 February 2025
Line 270:		Line 270:
	<span id="07"></span>		<span id="07"></span>

	=A Bethe-Salpeter based F<sub>xc</sub>(yambo -o c -k lrc) =		=A Bethe-Salpeter based F<sub>xc</sub>(yambo -o c -k lrc -V qp) =

	As for TDDFT we might be a little bit disappointed at this stage as the only method that yields a reasonable absorption spectrum for LiF is based on MBPT. It is possible, however, to extract from the BS kernel a possible approximation for the xc-kernel. This approach is efficient, but is far too complicated, and requires the prior computation of the BS kernel. An alternative possibility is to use a simple Long Range Component model, as introduced in [[#Reining\|Reining]]. In this model, the yambo input file ''Inputs/07_LRC'' describes a model where		As for TDDFT we might be a little bit disappointed at this stage as the only method that yields a reasonable absorption spectrum for LiF is based on MBPT. It is possible, however, to extract from the BS kernel a possible approximation for the xc-kernel. This approach is efficient, but is far too complicated, and requires the prior computation of the BS kernel. An alternative possibility is to use a simple Long Range Component model, as introduced in [[#Reining\|Reining]]. In this model, the yambo input file ''Inputs/07_LRC'' describes a model where
Line 285:		Line 285:

	<span id="exercises"></span>		<span id="exercises"></span>

	= Additional Exercises =		= Additional Exercises =