ENCUTGWSOFT: Difference between revisions

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This  usually leads to much smoother energy-volume curves in AC-FDT and MP2 calculations.
This  usually leads to much smoother energy-volume curves in AC-FDT and MP2 calculations.
The modified Coulomb kernel is in this case:
The modified Coulomb kernel is in this case:
<math>
<math>v_{\bf G} = \frac{4 \pi e^2} {| \bf G|^2} \frac{1}{2} \left( 1 + {\rm cos} \left( \pi \, \frac{ \frac{\hbar^2 |\bf G|^2 }{2 m_e} - {{TAG|ENCUTGWSOFT}}}{ {{TAG|ENCUTGW}} -  {{TAG|ENCUTGWSOFT}}} \right) \right)  
v_{\bf G} = \frac{4 \pi e^2} {| \bf G|^2} \frac{1}{2} \left( 1 + {\rm cos} \left( \pi \, \frac{ \frac{\hbar^2 |\bf G|^2 }{2 m_e} - {{TAG|ENCUTGWSOFT}}}{ {{TAG|ENCUTGW}} -  {{TAG|ENCUTGWSOFT}}} \right) \right)  
\qquad \mbox{for} \quad  \frac{\hbar^2 |\bf G|^2 }{2 m_e} >  {{TAG|ENCUTGWSOFT}}</math>  
\qquad \mbox{for} \quad  \frac{\hbar^2 |\bf G|^2 }{2 m_e} >  {{TAG|ENCUTGWSOFT}}</math>  



Revision as of 17:29, 15 January 2017

ENCUTGWSOFT = [real] (energy cutoff for response function)
Default: ENCUTGWSOFT = ENCUTGW for ALGO=ACFDT 


\begin{tabular} {ll} Default: \\ {\tt ENCUTGWSOFT}={\tt ENCUTGW}$\times 0.8$ & for {\tt ALGO}=ACFDT \\ {\tt ENCUTGWSOFT}={\tt ENCUTGW} & else \\ \end{tabular} \vspace{5mm}

The flag allows to truncate the Coulomb kernel slowly between the energy specified by ENCUTGWSOFT and ENCUTGW. This usually leads to much smoother energy-volume curves in AC-FDT and MP2 calculations. The modified Coulomb kernel is in this case:


Related Tags and Sections

PRECFOCK, ENCUT, ENCUTGW, GW calculations


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