EPW Forum

Hi Jykun, The error message explains clearly "coarse k-mesh needs to be strictly positive in 1st BZ". The uniform k-mesh you have provided in the 'nscf.in' are not positive in the 1st BZ, need to define a homogeneous k-grid. I suggest, the homogeneous k grid for the non self-consistent calculations ...

Hi Shubham,

That's great.

Happy EPWing,
Hari

Hi Shubham, Could you double check your nscf.out file if it has 216 k-points printed or not? Sometimes, because of symmetry, QE prints more number of k-points that the supplied. If it is so, I recommend using 'calculation = 'bands'' instead of 'nscf' in the nscf.in. I hope it helps. Happy EPWing, Hari

Hi Shubham, It looks like your calculations are not converged with respect to number of Mastubara frequency points. What is the value of 'wscut' used (and 'nswi' at different temperature) in your calculations? As the temperature increases, the value of 'nswi' decreases with fixed 'wscut'. I recommen...

Hi NFH, It would be appreciated if you could sign your name and affiliation in your future posts. You can use asr_typ = 'no' in EPW with a small modification in the code as the following. 1) replace CALL set_asr2(asr_typ, nqc1, nqc2, nqc3, ifc, zstar, nat, ibrav_, tau_) by IF (asr_typ /= 'no') CALL ...

Hi Lavoisier, 1 and 2. The interpolated band/phonon looks good. In the band structure, the top and bottom bands with PW are not included in the wannierization, so you do not see in the EPW calculation. 3. I think, you need to read EPW documentation in more details. 4. No, EPW does not help improve t...

Hi Wenjiang,

On top of Sabya's question, could you send us your inputs/outputs and plots?

Happy EPWing,
Hari

Hi Timon,

Looks like your Pade approximation did not reach convergence. I recommend decreasing the value of npade (https://docs.epw-code.org/doc/Inputs.html#npade) in your input file. I hope it helps.

Happy EPWing,
Hari

Hi wqy1,

Please set 'ephwrite = .true.' in your input so that the XX.ephmat directory will be created and required data will be written to files to solve the Eluiashberg equations.

Happy EPWing,
Hari

Hi wqy1, It looks like you do not have required files to solve eliashberg equations. They are; 'egnv', 'freq', 'ephmatXX', and ikmap (inside Ca2H.ephmat directory in your case) and can be obtained by setting 'ephwrite = .true. It would have been easy for us to investigate your error if you could sha...