About the NVT ensemble

Dear LAMMPS users,

Recently I followed the simulation procedures in a literature. In this literature, NVT ensemble is employed. Also, the thermostat is through the Bussi thermostate (temp/csvr). I have the following questions.

#1 In the mannual, I have learned that the temp/csvr does not integrate the position of atoms, and thus a separate time integration fix should be used. I have used the NVE according to the mannual. My question is: Is the NVE + Bussi thermostat(temp/csvr) = NVT.

#2 In the literature, the relaxation constant is 0.1 ps. So which parameter is relative to this relaxation constant in the command temp/csvr. I have seen in some topics in the community and perhaps the Tdamp corresponds to the relaxation constant.

Thanks for your help!
Best regards,
Shusen Guo


  • #1 This is correct for some systems, but as stated in this forum before, using fix NVE + a thermostat (or fix NVT) does not enforce the NVT ensemble.

  • #2 Yes indeed, “the Tdamp parameter is specified in time units and determines how rapidly the temperature is relaxed”, from the csrv page.


Hello Simon,
Really appreciate for your kindly help. This really solves my problems!

Best regards,
Shusen Guo