questions about the dielectric constant of silicon.

[irene33039]

Hello, I am a student from TsingHua University, Taiwan, recently I am using Quantum Espresso to simulate the dielectric constant of materials, I saw that you have shared the simulation results of silicon, but I will provide you with the code for silicon simulation, but it is not the same as the result of the dielectric constant graphs, I will change the kpoint in the nscf to 6 6 6 6 0 0 0 in order to comply with your results, I would like to ask what may be the cause of this? I would like to ask what could be the cause of this.
Thank you for your help!

[pranabdas]

Hi @irene33039, it is possible that my calculation did not converge with k-grid (and I mixed up some input/output files). I see in epsilon.x manual that automatic k-grid option does not work https://gitlab.com/QEF/q-e/-/blob/develop/PP/Doc/eps_man.pdf I will look into it and repeat the calculation. Thank you.

[pranabdas]

@irene33039 your results are correct. I repeated the calculation and found my plot is obtained from 6 6 6 k-grid (not 30 30 30). Thank you.