[Pw_forum] NMR Gipaw Calculations

[Davide Ceresoli]

Dear Alan,
     I would try to reach an absolute error of the order of
0.001 on the f-sum rule, for systems up to ~100 electrons.
I never investigated whether an absolute or relative error
is the right choice.

Best regards,
     Davide



On 09/21/2017 07:41 PM, Ambrozio wrote:
> Hi dear users and developers,
> 
> I have a question regarding the chemical shielding convergence using Gipaw. As 
> the best of my knowledge, the f-sum rule parameter is an indicative of the 
> convergence, corresponding to the number of valence electrons. I use a criterion 
> of 0.01 for the absolute error in the f-sum rule tensor  principal components. 
> I'd like to know if this criterion is correct? I mean ... should I take the 
> absolute error ? or the relative one?
> 
> Regards,
> 
> Alan,
> 
> Federal University of Espirito Santo, Vitoria, Brazil.
> 
> -- 
> 
> Alan J. Romanel Ambrozio
> Bacharel em Física
> Mestre em Eng. de Materiais
> Doutorando em Física - PPGFis
> 
>