usage of two different lattices with two different structures(fcc, Wurtzite) in same simulation box

Dear Lammp_User:
I am new to this forum, I am using this lammps software from few days. I want to built
a structure with two different lattices & with two different structures (example fcc & Wurtzite) in the same simulation box.
I modified the code for wurtzite structure. But the problem with the lammps simulation is when I was simulating the system
with the two different lattices in the same simulation box ,the system is melting down at 300K only. I don’t know whats wrong in the system.
Where as when I was simulating the system with individual lattice constants in separate simulation box it is working good, but when I was combining
two gether in same simulation box it is melting down. If some one could able to show solution for this problem I am so grateful. I have attached the input script
as well as the potential files used in my simulation.

Thank you,

Alloy.txt (1.08 KB)

GaN_tersoff.txt (1.52 KB)

Al_tersoff.txt (748 Bytes)

Assuming you built the hetero-structure correctly,
which is up to you to figure out, then these lines

pair_style tersoff
pair_coeff * * AlN.tersoff_vamsi Al Al Al
pair_coeff * * GaN.tersoff Ga N Ga

don't make sense. The 2nd pair coeff will
simply override the first. I don't know what
you want to do with 2 Tersoff potentials,
but you could look at the pair hybrid command,
or you could build a single Tersoff potential
file that has the params for all 3 elements.