Dear Prasad Matukumilli,
I did not participate in the work on this paper, so please interpret my answer as suggestion only. If you need a more in-depth answer please contact the authors of the article.
I would set up the T(2) data set as input
ML_AB in a separate run of VASP with
and tune the
ML_EPS_LOW parameter in such way that the desired reduction is achieved. In the paper, the original T(2) set was compressed from 1275 to 168 structures. I assume that this was done by applying the "
select" mode and then picking only the structures from the resulting
ML_ABN file for which local reference configurations were selected. This requires some scripting work, because these structures are not directly extracted from the data set by VASP. However, you can find the structure indices in the
ML_ABN file in the first column of the "
Basis set for ..." section. For example, let's assume your T(2) set looks like this
Code: Select all
...
**************************************************
The number of configurations
--------------------------------------------------
1275
...
**************************************************
The numbers of basis sets per atom type
--------------------------------------------------
3212
**************************************************
Basis set for H
--------------------------------------------------
1 1
1 2
1 6
2 1
2 17
29 13
...
Here you can see that structures 1, 2, 29,... contain local reference structures, i.e., atoms selected as reference environments. In this examples these atoms are:
Code: Select all
structure 1: atom 1
structure 1: atom 2
structure 1: atom 6
structure 2: atom 1
structure 2: atom 17
structure 29: atom 13
...
After running with
ML_MODE = select you should find a reduced set of local reference configurations in the
ML_ABN file, e.g.:
Code: Select all
...
**************************************************
The number of configurations
--------------------------------------------------
1275
...
**************************************************
The numbers of basis sets per atom type
--------------------------------------------------
523
**************************************************
Basis set for H
--------------------------------------------------
1 6
64 23
...
Now, only structures 1, 64,... contain reference atoms whereas structures 2 and 29 were removed by CUR selection. So the task at this point is to extract the configurations with the given indices and convert them into the
POSCAR format with a script. Then, run your low- and high-level ab initio calculations and construct the T(3) data set.
Hope this helps, if there are further questions please open a new topic!
Best,
Andreas Singraber