nvt-tdamp

Hi everyone,

I want to simulate heating up for copper. The system size is 444.
The setting of input script is as follows.

fix 1 all nvt temp 0 100 0.4 drag 0.2
timestep 0.005
run 1000

the result after running appears -nan in its log.lammps.
Then the setting is replaced by the following.

fix 1 all nvt temp 100 100 0.4 drag 0.2
timestep 0.005
run 1000

its result after running can not reach 100 k, only 0.0005 K, in 1000 steps.

According to the manual of LAMMPS, “A good choice for many models is a Tdamp of around 100 timesteps.”
I don’t know where the above question is. How many is Tdamp in general?

Best regards,
Pan

Hi everyone,

I want to simulate heating up for copper. The system size is 4*4*4.
The setting of input script is as follows.

fix 1 all nvt temp 0 100 0.4 drag 0.2
timestep 0.005
run 1000

the result after running appears -nan in its log.lammps.
Then the setting is replaced by the following.

fix 1 all nvt temp 100 100 0.4 drag 0.2
timestep 0.005
run 1000

its result after running can not reach 100 k, only 0.0005 K, in 1000 steps.

1000 time steps is practically the same as instantaneous. Just set the
temperature via the velocity command.

According to the manual of LAMMPS, "A good choice for many models is a Tdamp of around 100 timesteps."
I don't know where the above question is. How many is Tdamp in general?

I don't understand what you don't understand. The wording is concise.

In general, a nose-hoover thermostat cannot be rushed and what you are
trying is "brutal". So no surprise it doesn't do what you are trying
to force it to do.

Axel