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The ppa

Posted: Mon Nov 08, 2010 2:44 am
by sdwang
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

Re: The ppa

Posted: Mon Nov 08, 2010 9:19 am
by Daniele Varsano
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