[QE-users] Wrong phonon dispersion (Au) along X-K direction

[Stefano de Gironcoli]

Dear Md. Jahid Hasan Sagor,

    usually when drawing a dispersion plot in an fcc crystal the bit 
that goes from \Gamma to X passing through K is a dispersion calculated 
along the so called \Sigma direction with  k=(\csi, \csi, 0) which for 
\csi=0 is \Gamma, for \csi=0.75 is K and for \csi=1.0 is (1.0,1.0,0.0) = 
(0.0,0.0,1.0)-(1.0,1.0,1.0) which is equivalent to X. This is also why 
the length of the K-X panel is typically 1/3 of the one of the \Gamma-K 
panel.

  stefano de Gironcoli

On 30/10/24 19:36, Md. Jahid Hasan Sagor wrote:
> Hi,
>
> I calculated phonon dispersion and compared it with other studies. 
> However, dispersion is matched with every k direction except X-K. 
> Would you please tell me how to solve the issue? Should I use a 
> different pseudopotential? I am sharing here the details calculation 
> if you can help.
> Here is my result. At K, the graph is not smooth at all. When I 
> compared with other studies, I found the mismatch along the X-K 
> direction.
>
> image.png
> Here is my scf.in <http://scf.in/>
> image.png
> Here is my ph.in <http://ph.in/>
> image.png
> Here is my q2r.in <http://q2r.in/>
> image.png
> And finally, this is matdyn.x
> image.png
>
> Thank you so much. I used plotband.x and gnuplot to plot the 
> dispersion curve.
>
> Best
> Md Jahid Hasan Sagor
> PhD student
> Mechanical Engineering
> University of Maine
>
>
> _______________________________________________
> 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 listusers at lists.quantum-espresso.org
> https://lists.quantum-espresso.org/mailman/listinfo/users
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.quantum-espresso.org/pipermail/users/attachments/20241031/16d6a929/attachment.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image.png
Type: image/png
Size: 25073 bytes
Desc: not available
URL: <http://lists.quantum-espresso.org/pipermail/users/attachments/20241031/16d6a929/attachment.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image.png
Type: image/png
Size: 65469 bytes
Desc: not available
URL: <http://lists.quantum-espresso.org/pipermail/users/attachments/20241031/16d6a929/attachment-0001.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image.png
Type: image/png
Size: 20820 bytes
Desc: not available
URL: <http://lists.quantum-espresso.org/pipermail/users/attachments/20241031/16d6a929/attachment-0002.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image.png
Type: image/png
Size: 8142 bytes
Desc: not available
URL: <http://lists.quantum-espresso.org/pipermail/users/attachments/20241031/16d6a929/attachment-0003.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image.png
Type: image/png
Size: 17909 bytes
Desc: not available
URL: <http://lists.quantum-espresso.org/pipermail/users/attachments/20241031/16d6a929/attachment-0004.png>