units metal
dimension       3
boundary         p p s
atom_style      atomic
neigh_modify exclude type 2 3
neigh_modify exclude type 1 3
region         whole block -40 40 -60 60 -60 60  units box 
create_box      3 whole

lattice fcc 4.05
region middle  block -10 -1 -5 5 -5 0  #units box
create_atoms 3 region  middle

lattice wurtzite 3.189
region lower  block -10 -1 -5 5 0 6 #units box
create_atoms 3 region lower  basis 1 1 basis 2 1 basis 3 2 basis 4 2

#lattice wurtzite 3.112
#region middle  block -10 10 -10 10 -10 -0.1  #units box
#create_atoms 3 region  middle basis 1 3 basis 2 3 basis 3 2 basis 4 2


mass            1 69.45 # Gallium
mass            2 14.01 # Nitrogen
mass            3 26.98 # Allumium

#group GaN region lower #GaN
#group AlN region middle #AlN
#group boundary union AlN GaN

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

velocity all create 300 102456 dist uniform
fix 1 all nve
#fix 1 all nvt temp 300.0 300.0 100.0
timestep        0.001
thermo          100

dump            1 all atom 100 dump.expInGaN
run            20000