Hello

To obtain the projected density of states for a particular atomic orbital you 
calculate  a weighted density of states , using as weight the square modulus  
of the
projection of the wave-function to the atomic orbital.  In quantum-espresso 
this is done with the program projwfc.x

So  normal DOS is

[cid:[email protected]]

The projected density of states is

[cid:[email protected]]

Hope this helps
Best regards, Pietro

Sent from Mail<https://go.microsoft.com/fwlink/?LinkId=550986> for Windows

From: KRISHNENDU MUKHERJEE<mailto:[email protected]>
Sent: Wednesday, November 30, 2022 11:23 AM
To: users<mailto:[email protected]>
Subject: [QE-users] Parallelization and Input/Output of wfc in QE


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 BonfĂ 
UniversitĂ  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 />//




_______________________________________________
The Quantum ESPRESSO community stands by the Ukrainian
people and expresses its concerns about the devastating
effects that the Russian military offensive has on their
country and on the free and peaceful scientific, cultural,
and economic cooperation amongst peoples
_______________________________________________
Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
users mailing list [email protected]
https://lists.quantum-espresso.org/mailman/listinfo/users

Reply via email to