Dear all:
In my calculation, I allways used "PPAPntXPp=27.21138 eV" as it default value,but I want to kwon if this ppa value can affect the GW results, if so, how can I chose the ppa value?
Thanks!
SDWang
The ppa
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Daniele Varsano
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Re: The ppa
Dear Shudong,
in the case where the ppa is valid, the qp energies should not be affected by the PPAPntXPp value.
In the Ppa you are fitting the dielectric function with a single pole (plasmon frequency), and you are calculating
the \eps-1 at 0 and PPAPntXPp imaginary frequency, so the important issue is that such values is higher in energy
than the plasmon frequency. You can check it calculating the eels in linear response o.eel....
Cheers,
Daniele
in the case where the ppa is valid, the qp energies should not be affected by the PPAPntXPp value.
In the Ppa you are fitting the dielectric function with a single pole (plasmon frequency), and you are calculating
the \eps-1 at 0 and PPAPntXPp imaginary frequency, so the important issue is that such values is higher in energy
than the plasmon frequency. You can check it calculating the eels in linear response o.eel....
Cheers,
Daniele
Dr. Daniele Varsano
S3-CNR Institute of Nanoscience and MaX Center, Italy
MaX - Materials design at the Exascale
http://www.nano.cnr.it
http://www.max-centre.eu/
S3-CNR Institute of Nanoscience and MaX Center, Italy
MaX - Materials design at the Exascale
http://www.nano.cnr.it
http://www.max-centre.eu/