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lammps/examples/ASPHERE/star/in.star
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# SRD diffusion demo - rigid star particles
units lj
atom_style sphere
atom_modify map array first big
dimension 2
# read in clusters of rigid bodies
fix molprop all property/atom mol
read_data data.star fix molprop NULL Molecules
set type 1 mass 1.0
group big type 1
velocity big create 1.44 87287 loop geom
# equilibrate big particles
pair_style soft 1.12
pair_coeff 1 1 0.0
pair_coeff 2 2 0.0 0.0
pair_coeff 1 2 0.0 0.0
variable prefactor equal ramp(0,60)
fix soft all adapt 1 pair soft a * * v_prefactor
neighbor 0.3 bin
neigh_modify delay 0 every 1 check yes
fix 1 big rigid molecule
fix 2 all enforce2d
#dump 1 all atom 10 dump.star.equil
compute tbig all temp/sphere
thermo_modify temp tbig
thermo 100
run 1000
#undump 1
unfix soft
unfix 1
unfix 2
# add small particles as hi density lattice
region plane block INF INF INF INF -0.001 0.001 units box
lattice sq 85.0
create_atoms 2 region plane
set type 2 mass 0.1
group small type 2
velocity small create 1.0 593849 loop geom
# delete overlaps
# must set 1-2 cutoff to non-zero value
pair_style lj/cut 2.5
pair_coeff 1 1 1.0 1.0
pair_coeff 2 2 0.0 1.0 0.0
pair_coeff 1 2 0.0 1.0 0.5
delete_atoms overlap 0.5 small big
# SRD run
reset_timestep 0
neighbor 0.3 bin
neigh_modify delay 0 every 1 check yes
comm_modify mode multi group big vel yes
neigh_modify include big
# no pairwise interactions with small particles
pair_style lj/cut 2.5
pair_coeff 1 1 1.0 1.0
pair_coeff 2 2 0.0 1.0 0.0
pair_coeff 1 2 0.0 1.0 0.0
# use fix SRD to push small particles out from inside big ones
# if comment out, big particles won't see SRD particles
timestep 0.001
fix 1 big rigid molecule
fix 2 small srd 20 big 1.0 0.25 49894 shift yes 54979 &
search 0.2 collision slip inside ignore overlap yes
fix 3 all enforce2d
# diagnostics
uncompute tbig
compute tbig big temp/sphere
variable pebig equal pe*atoms/count(big)
variable ebig equal etotal*atoms/count(big)
thermo_style custom step temp f_2[8] etotal v_pebig v_ebig press &
f_2[1] f_2[2] f_2[3] f_2[4] f_2[5] &
f_2[6] f_2[7] f_2[8] f_2[9] f_2[10] f_2[11] f_2[12]
thermo_modify temp tbig
thermo 1000
#dump 1 all atom 1000 dump.star
#dump 1 all image 1000 image.*.jpg type type zoom 1.6
#dump_modify 1 pad 6 adiam 1 1 adiam 2 0.2
run 100000
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