[QE-users] Parallelization and Input/Output of wfc in QE

[KRISHNENDU MUKHERJEE]

Dear Dr. Pietro, 

Thank you for your reply. I did not have a course on Quantum Mechanics and Solid State Physics. But I am currently reading thoroughly text books on those subjects. I have another question. 
In Quantum Espresso the electron is considered to be described by plane-waves. So, it does not have information regarding its belongness to any particular s,p or d orbital. However, I have seen articles with Quantum Espresso results with DOS for a particular orbital (e.g., 3d). Can you kindly let me know how DOS of a particular orbital can be obtained from the plane-wave representation of electron? 

Thank you, 
Best regards, 
Krishnendu 

------------------------------------------------------------------------------------------------------------------------------------------------------- 

Dear Krishnendu, 

if you want to know what the grids are (those appearing in the header of 
the table) check this message from Stefano de Gironcoli: 

https://lists.quantum-espresso.org/pipermail/developers/2017-November/001783.html 

The second keyword in that table is "sticks", which concerns with the 
way the data is distributed among multiple processes in order to perform 
a parallel FFT. This presentation, again by Prof. de Gironcoli, will 
explain how that works: 

https://www.youtube.com/watch?v=YqYdu1aVi-o 

With these information and the details of your input file (ecutwfc, 
ecutrho and the lattice) you should be able to roughly predict the 
number of G-vectors of the various grids of your plane wave expansion. 
Predicting the number of sticks is slightly more complicated and, in my 
opinion, it's quite pointless. 

Best wishes, 
Pietro 

--- 

Pietro Bonfà 
Università di Parma 


On 11/29/22 12:56, KRISHNENDU MUKHERJEE wrote: 
> 
> How many G-vectors are required to describe a plane-wave ? 
> 
> It will be very helpful if I could understand the following part of the 
> output that I am getting almost in the beginning. 
> 
> G-vector sticks info 
> -------------------- 
> sticks: dense smooth PW G-vecs: dense smooth PW 
> Sum 6181 3093 885 364637 128843 20341 
> 
> Thank you, 
> Regards, 
> 
> Krishnendu 
> 
> ------------------------------------------------------------------------------------------------------------------------------------------ 
> 
> Actually, all the coefficients of all the wavefunctions AT A GIVEN K 
> POINT: there is one wavefunction file per k point. 
> 
> Paolo 
> 
> On 11/28/22 14:07, Riccardo Piombo uniroma1 via users wrote: 
>>/So in a single file QE stores ALL the coefficients of ALL the wfcs? />//>/Is it correct? />//>//>/Thanks for your help, />//>/Riccardo Piombo />// 




-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.quantum-espresso.org/pipermail/users/attachments/20221130/002b032e/attachment.html>