I'm simulating a Lenard Jones fluid with LAMMPS. I already have the simulation but I have the problem of recovering data. I'm interested in pressure vs time, pressure vs position, temperature vs time, total and potential energy vs time, density vs position, surface tension, and capillarity force of the interphase.

The reason for doing this question is to know if LAMMPS has a report of these quantities or if I have to calculate them from the x,y,z,vx,vy,vz,fx,fy,fz information of each molecule in the simulation. In that case, does someone know how to calculate surface tension out of these quantities?


1 Answer 1


Temperature vs. time can be interrogated using an inbuilt command, documented here. The density and the total and potential energy can be reported as part of the thermodynamic output if given as arguments to thermo_style.

Once you have temperature and density you will need to use an equation of state to calculate the pressure. A review of different proposed equations of state for LJ fluid is here.

A calculation of the surface tension is described in this paper.


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.