LSCK: Difference between revisions

Latest revision as of 08:41, 29 August 2024

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

Important: Up to vasp.6.2, the default was LSCK= .TRUE.

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

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

${\displaystyle v_{G} = 4 \pi e^2 \frac{ (G_{max}-G_{min})(G_{max}-G) }{ (G_{min}^2 - G(2G_{min}-G_{max}))^2 } \qquad \mbox{for} \quad \mathrm{ENCUTGWSOFT}=\frac{\hbar^2G_{min}^2}{2m_e}<\frac{\hbar^2 G^2}{2m_e}<\frac{\hbar^2G_{max}^2}{2m_e}=\mathrm{ENCUTGW}}$

This kernel 'squeezes' the contributions from large wave vectors $G>G_{max}$ into the window given by ENCUTGWSOFT. Effectively, this extrapolates the random-phase-approximation–correlation energy to the ENCUTGW $\to \infty$ limit, assuming that the basis-set-incompleteness error falls off as $1/$ ENCUTGW $^{3/2}$ .

@@ Line 1: / Line 1: @@
 {{TAGDEF|LSCK|[logical]| .FALSE.}}
-----
+{{NB|important|Up to vasp.6.2, the default was {{TAG|LSCK}}{{=}} .TRUE.}}
-If {{TAG|LSCK}} is set to .TRUE., the squeezed Coulomb kernel is used instead of the [[ENCUTGWSOFT|cosine window]]:{{cite|riemelmoser:jcp:2020}}
+----Description: {{TAG|LSCK}}=.True. switches on the squeezed Coulomb kernel.
+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{
@@ Line 10: / Line 11: @@
 \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 articles ==
 {{TAG|ENCUTGW}},
 {{TAG|GW calculations}}
+{{TAG|ACFDT/RPA calculations}}
 {{sc|LSCK|Examples|Examples that use this tag}}
 ----
-[[The_VASP_Manual|Contents]]
-[[Category:INCAR]][[Category:Many-Body Perturbation Theory]][[Category:GW]][[Category:ACFDT]]
+[[Category:INCAR tag]][[Category:Many-body perturbation theory]][[Category:GW]][[Category:ACFDT]]