ML FF EATOM
ML_FF_EATOM = [real array]
Default: ML_FF_EATOM = 0.0
Description: Reference total energies of isolated atoms used in the machine learning force field method.
This tag is only used if ML_FF_ISCALE_TOTEN_MB=1.
Although by not setting this tag accurate force fields can be produced, it is recommended to set this values to the appropriate values calculated by VASP. Each reference energy should be obtained from a VASP calculation of an isolated atoms in a sufficiently large simulation box. The reference is then simply taken from the Helmholtz free energy from the OSZICAR file (value following "1 F=" in that file).
The reference energies are simply set in one line as a list for each species, i.e. like the following
ML_FF_EATOM = E_1 E_2 E_3 ...
where E_1, E_2, E_2 etc. are the energies for species 1, 2, 3 etc. (corresponding to the order they occur in the POTCAR file).
The unit of the energy is eV/atom.