Dear Ben,
what is the E - E' difference you are referring to ?
Is it the difference between the two estimates of the energy ("total
energy" and "Harris-Foulkes estimate") ?
If so, the first is the expression of the TE from the variational
principle and is an upper bound to the scf result (no
Stefano,
Thanks for the details, I think we have the definitions sorted out. But why is
the E - E' from the output file not approximately equal to the estimated SCF
accuracy? It seemed there is always some multiplicative factor difference
between 1-20.
On 9/28/19 12:51 PM, Stefano de Gironcoli
Dear Ben,
I think you are right on both accounts... thanks for pointing out the
problem in eq A7
the equation in reciprocal space equivalent to A6 and correctly coded
in PW/src/scf_mod.f90 in function rho_ddot (lines ~450 - 490 )
0.5 4pi e^2 Omega \sum |Delta_rho|^2/|G|^2
it has the corre
I figured the code had to be correct, and are equations A.6 and A.7 equivalent?
It's not trivially obvious that they would be equal as one is an integral in
real space whereas the other is an integral in reciprocal space. If they are
the same it looks like A.7 might be missing the volume factor
On Thu, Sep 26, 2019 at 9:44 PM Ben Comer wrote:
> Just a quick follow up, the text seems to imply that A7 is used rather
> than A6. do you know where this is defined in the source code?
>
Variable dr2 in PW/src/mix_tho.f90, routine rho_ddot in PW/src/scf_mix.f90
Paolo
> On 9/26/19 10:57 AM, Pa
Just a quick follow up, the text seems to imply that A7 is used rather than A6.
do you know where this is defined in the source code?
On 9/26/19 10:57 AM, Paolo Giannozzi wrote:
If I remember correctly: Eq.A6 of J.Phys.: Condens. Matter 21, 395502 (2009)
Paolo
On Thu, Sep 26, 2019 at 4:52 PM Be
Thanks this answered my question, the responses are much appreciated!
On 9/26/19 10:58 AM, Stefano de Gironcoli wrote:
> In the simplest case it is the electrostatic self energy of the
> difference between rho_in and rho_out and as such it is an estimate of
> the energy error. in more complex ca
If I remember correctly: Eq.A6 of J.Phys.: Condens. Matter 21, 395502 (2009)
Paolo
On Thu, Sep 26, 2019 at 4:52 PM Ben Comer wrote:
> Hello,
>
> I'm trying to understand what exactly estimated SCF accuracy is. Does
> anyone know where I can find a formal definition of what it is and how
> it is
Hello,
I'm trying to understand what exactly estimated SCF accuracy is. Does
anyone know where I can find a formal definition of what it is and how
it is being calculated? The structure of the output file implies that it
is related to the Harris-Foulkes and the total energy, but it is clearly
