LSCK: Difference between revisions

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{{TAGDEF|LSCK|[logical]| .FALSE.}}
{{TAGDEF|LSCK|[logical]| .FALSE.}}
Description: {{TAG|LSCK}}=True switches on the use of the squeezed Coulomb kernel.
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If {{TAG|LSCK}} is set to .TRUE., the squeezed Coulomb kernel is used instead of the [[ENCUTGWSOFT|cosine window]]:{{cite|riemelmoser:jcp:2020}}
If {{TAG|LSCK}} is set to .TRUE., the squeezed Coulomb kernel is used instead of the [[ENCUTGWSOFT|cosine window]] {{cite|riemelmoser:jcp:2020}}:


<math>v_{G} = 4 \pi e^2 \frac{
<math>v_{G} = 4 \pi e^2 \frac{
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\qquad \mbox{for} \quad  \mathrm{ENCUTGWSOFT}=\frac{\hbar^2G_{min}^2}{2m_e}<\frac{\hbar^2 G^2}{2m_e}<\frac{\hbar^2G_{max}^2}{2m_e}=\mathrm{ENCUTGW}</math>  
\qquad \mbox{for} \quad  \mathrm{ENCUTGWSOFT}=\frac{\hbar^2G_{min}^2}{2m_e}<\frac{\hbar^2 G^2}{2m_e}<\frac{\hbar^2G_{max}^2}{2m_e}=\mathrm{ENCUTGW}</math>  


This kernel ''squeezes'' contributions from large wave vectors <math>G>G_{max}</math> into the window given by {{TAGBL|ENCUTGWSOFT}}. Effectively, this extrapolates the RPA correlation energy to the {{TAG|ENCUTGW}} <math>\to \infty</math> limit, assuming that the basis set incompleteness error falls off as <math>1/\mathrm{ENCUTGW}^{3/2}</math>.
This kernel 'squeezes' the contributions from large wave vectors <math>G>G_{max}</math> into the window given by {{TAG|ENCUTGWSOFT}}. Effectively, this extrapolates the random-phase-approximation&ndash;correlation energy to the {{TAG|ENCUTGW}} <math>\to \infty</math> limit, assuming that the basis set incompleteness error falls off as <math>1/</math>{{TAG|ENCUTGW}}<math>^{3/2}</math>.
== Related Tags and Sections ==
== Related Tags and Sections ==
{{TAG|ENCUTGW}},
{{TAG|ENCUTGW}},

Revision as of 14:28, 20 December 2021

LSCK = [logical]
Default: LSCK = .FALSE. 

Description: LSCK=True switches on the use of the squeezed Coulomb kernel.


If LSCK is set to .TRUE., the squeezed Coulomb kernel is used instead of the cosine window [1]:

This kernel 'squeezes' the contributions from large wave vectors into the window given by ENCUTGWSOFT. Effectively, this extrapolates the random-phase-approximation–correlation energy to the ENCUTGW limit, assuming that the basis set incompleteness error falls off as ENCUTGW.

Related Tags and Sections

ENCUTGW, GW calculations ACFDT/RPA calculations

Examples that use this tag


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