Materials studio to lammps data file

I’ve created a structure of water droplet falling into Cu surface using material studio. I’m trying to convert material studio file using msi2lmp into lammps lmp data file. But, I’m getting this:

Running msi2lmp v3.9.9 / 05 Nov 2018

Forcefield: Class I
Forcefield file name: /usr/share/lammps/frc_files/cvff.frc
Output is recentered around geometrical center
Output contains style flag hints
System translated by: 0 0 0
Reading car file:
Reading mdf file: Cu_H2O.mdf

Building internal coordinate lists

Reading forcefield file

Get force field parameters for this system
Unable to find mass for xx

No datafile has been created. I’ve seen that in older version of material studio, they’ve got a module named Discovery tools, in which they’ve converted it to cvff forcefield. But, in newer version of materials studio, this module is absent. How can I use msi2lmp or another module in material studio 2020?

I think you will get better support if you post on LAMMPS forum.

From my personal experience, I don’t recommend using materials studio to build models. This kind of way is a bit old-fashioned and requires a lot of time effort to debug. Also there is no big community to provide support.

With that said, the error you found might be solved if you provide correct species name in your input files that matches the atomic species in CVFF force fields. “Unable to find mass for xx” means in your input files some atoms are without name or named xx