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Dear
I met a question when I used the vasp MLFF in lammps as the third-party software.
How to select the atom_style for oragnic liquid or solid? atomic or full.
If I select full for organic liquid, I need to constrain H atom using fix shake, but need to define the bond_style.
How to define the bond_style in vasp MLFF?
For solid, I select the atomic for atom_style, but I can not contrain the H atom by fix shake?
yours
Hello!
As far as I know there is nothing special about the VASP MLFF pair style inside LAMMPS with respect to bonds. Hence, it should be possible to set up bonds and constraints in the usual ways this can be done in LAMMPS. I have not done this myself yet, but I guess if you intend to use the SHAKE algorithm to constrain certain atom distances you need first to define at least one bond type and the individual bonds in your LAMMPS data input file. Here is an example. Note how there are additional lines with 1600 bonds and 1 bond types in the header. Also, after the Atoms section there comes a Bonds section defining each individual bond between two atoms (starting in line 5619 in the example file). After you have added these explicit bonds in the data file you should be able to use the fix shake command to constrain these bonds (with constraints sub-command "b ..."). As you mentioned this will most likely require a atom_style full setup. What I really do not know is whether you still have to define a "dummy" bond_style in your LAMMPS script, my guess is no... but please direct any further questions about this topic to the LAMMPS developers and study the relevant LAMMPS documentation:
https://docs.lammps.org/read_data.html
https://docs.lammps.org/fix_shake.html
All the best,
Andreas Singraber
thank you ,
I can not open the link "Here is an example".
please reset it/
Sorry, I fixed the link now!