[lammps-users] problem of temperature

Hi,

There are two groups of particles in my system. one is mobile, the other is rigid .
I use fix rigid command and fix nve to control them respectively and only compute the mobile group temperature. The main in code is attached as follows.

The question is the temperature ~257 is not my target temperature 323. Why?

---------- in code,
compute WTem mobile temp/com
thermo 100
thermo_style custom step temp c_WTem etotal press vol
thermo_modify temp WTem

#WARNING: Temperature for thermo pressure is not for group all

fix cmov mobile nve/limit 0.1
fix fixnp nps spring tether 50.0 0.0 0.0 125 0.0
fix rigid nps rigid single
#1 rigid bodies with 1820 atoms
fix ctem mobile temp/berendsen 323.0 323.0 100.0
fix_modify ctem temp WTem
fix cpres all press/berendsen xy 0.98665 0.98665 0.98665 0.98665 0.98665 0.98665 200 modulus 33333
fix rmcm all momentum 1 linear 1 1 1 angular

Step Temp WTem TotEng Press Volume
40500 256.46911 256.46911 -555997.58 3.6872834 10644492
40600 256.48255 256.48255 -556240.18 -5.278607 10639306
40700 256.31262 256.31262 -556816.73 -0.72160846 10635685
40800 256.44469 256.44469 -557517.32 -3.5081848 10628716
40900 256.67241 256.67241 -557668.63 -2.9295446 10625770
41000 256.51335 256.51335 -557803.1 8.4521017 10623067
41100 256.34465 256.34465 -558836.95 -5.0019193 10614886

I don't know - I would debug this by turning off various
commands and seeing if you can start with a working
system as you add commands one at a time.

Steve