Dear All,

I’d like to use Es+ (Streitz, Mintmire , Phys. Rev. B 50, 1994) potential in LAMPPS, I found that similar one ReaxFF is already implemented. Has anyone used it for Aluminum oxides?

The ReaxFF options in LAMMPS are well documented. See the pair_style reax doc page.
If you have param files for other elements you can use them, but that is up to you.