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>v_{\bold{G}} = \frac{4 \pi e^2} {| \bold{G}|^2} \frac{1}{2} \left( 1 + {\ | <math>v_{\bold{G}} = \frac{4 \pi e^2} {| \bold{G}|^2} \frac{1}{2} \left( 1 + {\mathbf{cos} \left( \pi \, \frac{ \frac{\hbar^{2} |\bold{G}|^2 }{2 m_e} - {{TAG|ENCUTGWSOFT}}}{ {{TAG|ENCUTGW}} - {{TAG|ENCUTGWSOFT}}} \right) \right) | ||
\qquad \mbox{for} \quad \frac{\hbar^2 |\ | \qquad \mbox{for} \quad \frac{\hbar^2 |\bold{G}|^2 }{2 m_e} > {{TAG|ENCUTGWSOFT}}</math> | ||
<math>v_{\bold{G}} \frac{4 \pi e^2} {| \bold{G}|^2}</math> | <math>v_{\bold{G}} \frac{4 \pi e^2} {| \bold{G}|^2}{\rm cos}</math> | ||
== Related Tags and Sections == | == Related Tags and Sections == | ||
{{TAG|PRECFOCK}}, | {{TAG|PRECFOCK}}, | ||
Revision as of 19:32, 15 January 2017
ENCUTGWSOFT = [real] (energy cutoff for response function)
| Default: ENCUTGWSOFT | = ENCUTGW | for ALGO=ACFDT |
| = ENCUTGW | else |
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: Failed to parse (Conversion error. Server ("cli") reported: "[INVALID]"): {\displaystyle v_{\bold{G}} = \frac{4 \pi e^2} {| \bold{G}|^2} \frac{1}{2} \left( 1 + {\mathbf{cos} \left( \pi \, \frac{ \frac{\hbar^{2} |\bold{G}|^2 }{2 m_e} - {{TAG|ENCUTGWSOFT}}}{ {{TAG|ENCUTGW}} - {{TAG|ENCUTGWSOFT}}} \right) \right) \qquad \mbox{for} \quad \frac{\hbar^2 |\bold{G}|^2 }{2 m_e} > {{TAG|ENCUTGWSOFT}}}
Related Tags and Sections
PRECFOCK, ENCUT, ENCUTGW, GW calculations