#3d Lennard-Jones melt
variable x index 1
variable y index 1
variable z index 1
variable xx equal 10*$x # 10*10*10=1000 particles on a simple cubic lattice
variable yy equal 10*$y # 4*1000 = 4000 particles on a fcc lattice
variable zz equal 10*$z
variable dumpfreq equal 100 # dump snapshot frequency
variable thermofreq equal 100 # thermo output frequency
variable Tstart equal 2.0
variable Tend equal 2.0
variable Tdamp equal 0.1
variable rho equal 0.8 # number density N/V
variable dt equal 0.01
variable nsteps equal 10000
units lj
atom_style atomic
lattice fcc ${rho}
region box block 0 ${xx} 0 ${yy} 0 ${zz} # box range is from 0 to L
create_box 1 box
create_atoms 1 box
mass 1 1.0
velocity all create ${Tstart} 12345 loop geom
pair_style lj/cut 2.5
pair_coeff 1 1 1.0 1.0 2.5
neighbor 0.3 bin
neigh_modify delay 0 every 1 check yes page 100000
#neigh_modify delay 0 every 20 check no
fix 1 all nvt temp ${Tstart} ${Tend} ${Tdamp}
dump 1 all xyz ${dumpfreq} movie.xyz
dump_modify 1 element N
thermo ${thermofreq}
thermo_style custom step time temp ke etotal press vol spcpu cpuremain atoms
timestep ${dt}
run ${nsteps}