I have a question about how to incorporate U parameter for, let’s say, transition metal alloying. In maps, I know the magnetic moment can be applied to each atom by MAGATOM parameter. Is there anything similar to give each atom a U parameter automatically when the composition is changed, let’s say, from AC to AxB1-xC (A and B should have different U parameters)?
In ATAT, you can incorporate the U-related parameters under the [INCAR] section of your vasp.wrap file. You’ll need to specify the U value for each atomic type as explained in the VASP manual: https://cms.mpi.univie.ac.at/vasp/vasp/ … _DA_U.html
As you pointed out, the number of atomic species may vary across structures. You may need to write a wrapper to do this. E.g., generate VASP input file via "runstruct_vasp -nr" (-nr stands for do not run), edit the INCAR files, and then run.
You may be able to modify the file glue/vasp/ezvasp to implement the same syntax and mechanism as for the magnetic moment. The relevant lines to take inspiration from are: