Equilibration of core/shell using both Berendsen thermostat and Nose-Hoover barostat

Dear LAMMPS users,

As suggested in the manual the equilibration of core/shell should be done using a thermostat. e.g. Berendsen

Can the equilibration be done using both Berendsen thermostat and Nose-Hoover Barostat so the box relaxation can also be done simultaneously ?

I have tried to do that. The input script is given below. Please suggest me whether this is correct procedure or any modification has to done.


units metal
dimension 3
boundary p p p
atom_style full

#-----------------------ATOM DEFINITION----------------------------

#fix csinfo all property/atom i_CSID
read_data inp.xyz # fix csinfo NULL CS-Info

group cores type 1 2 3
group shells type 4 5 6

neighbor 2.0 bin
comm_modify vel yes

------------------------FORCE FIELDS------------------------------

kspace_style ewald 1.0e-6
pair_style buck/coul/long/cs 11.0 # A, rho, sigma=0, C, D

pair_coeff * * 0.0 1.0 0.0

pair_coeff 4 6 1545.21 0.3590 0.0 #La-O

pair_coeff 5 6 1267.50 0.3214 0.0 #Sr-O

pair_coeff 6 6 22764.3 0.1490 43.0 #O-O

bond_style harmonic
bond_coeff 1 145.0 0.0
bond_coeff 2 95.0 0.0
bond_coeff 3 42.0 0.0

------------------------ Equilibration Run -------------------------------

reset_timestep 0

thermo 100
thermo_style custom step temp pe etotal press vol cella cellb cellc cellalpha cellbeta cellgamma

compute CSequ all temp/cs cores shells
compute CSpress all pressure CSequ

thermo_modify temp CSequ

velocity bias option

velocity all create 1427 134 dist gaussian mom yes rot no bias yes temp CSequ
velocity all scale 1427 temp CSequ

fix thermoberendsen all temp/berendsen 1427 1427 0.4
fix NPH all nph iso 0.0 0.0 1.0
fix_modify thermoberendsen temp CSequ
fix_modify NPH press CSpress

1 fmsec timestep

timestep 0.001

run 100000

unfix thermoberendsen
unfix NPH

fix nve all nve

------------------------ Dynamic Run -------------------------------

dump 1 all custom 100 Trajectory id xu yu zu vx vy vz

run 100000



I don’t see any problem in principle with using
fix nph as a barostat in conjunction with the core shell
model and its thermostat. If no on else answers on the mail list,
I suggest you send an email to the author of
the CORESHELL package. His contact info
is in the src files or package documentation.


Thank You very much Steve for Your suggestion. I will do accordingly.