ELPH_POT_FFT_MESH

From VASP Wiki

ELPH_POT_FFT_MESH = [real real real] 

Description: Specifies the FFT mesh for mapping the electron-phonon potential to the primitive cell.


Once the electron-phonon potential has been computed in the supercell, it needs to be mapped to the primitive cell. By default, VASP chooses the primitive-cell FFT mesh to be consistent with the current ENCUT. However, sometimes it might be necessary to specify the FFT grid dimensions manually via ELPH_POT_FFT_MESH.

The chosen values must be the same as the desired NGX, NGY and NGZ of the electron-phonon calculation in the primitive cell.

Tip: In order to find the FFT grid dimensions corresponding to the primitive cell, you can start a minimal VASP calculation in the primitive cell and extract the values for NGX, NGY and NGZ from the OUTCAR file.

Related tags and articles

ELPH_POT_GENERATE, ELPH_POT_LATTICE, phelel_params.hdf5