Phelel params.hdf5

The phelel_params.hdf5 is used to calculate electron-phonon interactions via ELPH_RUN = True. It contains information related to the interatomic force constants and the derivative of the Kohn-Sham potential.

To generate the phelel_params.hdf5 file, you can either use the VASP internal driver via PHELEL_WRITE = True or use VASP in combination with phelel.