ENCUTGWSOFT
ENCUTGWSOFT = [real] (energy cutoff for response function)
| Default: ENCUTGWSOFT | = ENCUTGW[math]\displaystyle{ \times 0.8 }[/math] | 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: [math]\displaystyle{ 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} \gt {{TAG|ENCUTGWSOFT}} }[/math]
[math]\displaystyle{ v_{\bf G} }[/math]
Related Tags and Sections
PRECFOCK, ENCUT, ENCUTGW, GW calculations