Dev vasp kpointsopt

[the-hampel]

Convert KPOINTS_OPT/LOCPROJ_OPT data (along kpath) into dft_bands_input as it is possible for Wien2k and Elk. Auto-detect KPOINTS_OPT data during convert_dft_input.

Add dedicated SVO bands tests, and include minimal reproducibility inputs (INCAR/POSCAR/KPOINTS/KPOINTS_OPT/plo.cfg plus vaspout.h5).

Warning: this is based on a non released VASP version. So reproducibility of the provided vaspout.h5 is limited.

[harrisonlabollita]

Hi @the-hampel, thanks for this PR! This is a nice feature. While we are at, should we also add the high-symmetry path labels and x-ticks to the converter readers? For example, in Wien2k, the high-symmetry labels and high-symmetry points are printed at the end of the case.outband file. Our converters could be upgraded to read this and store in the hdf5. The user can then read data and metadata from the hdf5 file when making their plot. What do you think?

[the-hampel]

Hi @harrisonlabollita , yes that might be a good idea. Problem is that in VASP this is optional. A kpath is specified in the KPOINTS or KPOINTS_OPT file and might look like this:

k-points for bandstructure using Γ–X–M–Γ–R
100
line
reciprocal
  0.00000000   0.00000000   0.00000000 GAMMA
  0.00000000   0.50000000   0.00000000 X

  0.00000000   0.50000000   0.00000000 X
  0.50000000   0.50000000   0.00000000 M

  0.50000000   0.50000000   0.00000000 M
  0.00000000   0.00000000   0.00000000 GAMMA

  0.00000000   0.00000000   0.00000000 GAMMA
  0.50000000   0.50000000   0.50000000 R

Problem is that the 4 item in each coordinate is optional and you can write whatever you want. It is used by py4vasp and it is already stored by vasp into the vaspout.h5. So I can simply add this with a line of code to store it. But I shall add a check because the user can write there whatever. Where do we want to store it?

[harrisonlabollita]

Indeed, the same problem would occur in Wien2k. If the high-symmetry label is not indicated in their case.klist_band, we would not know it either. By default, we could just do K1,..., KN. My thought was just include in the dft_bands_input group. The field could be kpts_labels and kpts_labels_idx?

[the-hampel]

That sounds good. Let me instruct Mr Claude and we see how this looks.

[the-hampel]

7186a41 is a first draft. Let me know what you think and if this is compatible with wien2k.