[Pw_forum] NMR_shifts_selected_atoms

[Ari P Seitsonen]

Dear Kai,

   A quick reply from my side: The GIPAW method is slow in general, but the 
execution time does not depend strongly on the number of atoms. Therefore 
once the big calculation is done, to get the results for each atom is 
almost a byproduct; thus it would not help much to calculate the results 
only on fewer atoms.

   This is different in the converse NMR method, where the calculation on 
each atom would take long, but to calculate few atoms is much faster: This 
is so because there a small magnetic dipole is set on each target atom at 
a time and then a self-consistent calculation is performed; therefore here 
the calculation time practically scales with the number of atoms, each 
calculation being faster than the GIPAW calculation. The implementation of 
the converse NMR in QE has not yet been finished yet, so it is not in the 
public release at the moment.

     Greetings,

        apsi

-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-
   Ari Paavo Seitsonen / Ari.P.Seitsonen at iki.fi / http://www.iki.fi/~apsi/
     Ecole Normale Supérieure (ENS), Département de Chimie, Paris
     Mobile (F) : +33 789 37 24 25    (CH) : +41 79 71 90 935


On Tue, 9 Feb 2016, Kai Trepte wrote:

> Hello everyone,
>
> is it somehow possible to use the gipaw module for the calculation of NMR
> chemical shifts only on some atoms instead of all atoms in the system?
> Thus is there some keyword to restrict the evaluation of the chemical
> shifts to specific atoms in order to reduce calculation time?
>
> Best regards,
> Kai Trepte
>
>
> Kai Trepte
> Technische Universität Dresden
> Theoretische Chemie
> Bergstraße 66b
> 01062 Dresden
> _______________________________________________
> Pw_forum mailing list
> Pw_forum at pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>