Adding different structures in a training data set

[MusannaGalib]

Hello Nequip Team,
I have two questions regarding Nequip. Please help me with this.

1. I am confused about adding different structure types to the training dataset. For example, if an Alumina (Al2O3) has different types of defects, it will have different numbers of atoms. I want to build a potential that will capture the effects of multiple defects. I am confused about accommodating these different structures in the training file.

2. If I train a potential with Nequip, do I have to use Lammps with Allergo to run with mpi?

Thanks a lot!
MG