I met an error when trying to convert .car and .mdf into an lammps input file using the msi2lmp utility.
The error message says:
" Unable to find equivalent type for …
Unable to find torsion data for …
Unable to find oop data for …
Unable to find angle data for … "
The README file suggests that the error is related to the .frc file used. However, this .frc file works fine
for another similar .car file ( different structures and topologies, but same atom types ).
I found that sometimes you have to use CVFF forcefield in Material Studio so that the correct atom labels are assigned. For example, when you want to build an amorphous PE supercell, you have to build the chain from the “build” manual first, and then you use the “amorphous cell” component to build the amorphous supercell. At this second step, you choose CVFF forcefield. Then you export the constructed structure into .car file. It is possible that when you choose CVFF, the atom labels which can be recognized by msi2lmp are set. I found that if I chose COMPASS, msi2lmp gave me the same error. Hope this helps!