temperature in NVT

Dear all users of LAMMPS:

I want to prepare my system to be under an NVT ensemble. With the following input (with some help from here), I then check the temperature of the system. However, it is still about 200 K lower than the specified 1000 K (see below the figure, which centers around 800 K). My question is how to test/ verify that the NVT is a real/correct NVT? I think my input is reasonable. Thanks in advance.

Best regards
Jun

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I guess this temperature output is for the all atoms within the system.

You are assigning 1000 K temperature to ‘feslab’ group, not for all atoms.

Atoms in the ‘febottom’ group are fixed.

So average temperature would be less than 1000 K, which makes sense.

Sanjib

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Thanks.

However, I used “compute tslab feslab temp” to only calculate the temperature of the subsystem.

Best
Jun

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How you are getting the temperature data from this thermo_style?

thermo_style custom step pe ke etotal temp

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Wow, I think I know, I should use

thermo_style custom step pe ke etotal c_tslab

Thanks.
Best
Jun

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