Luciano Laratelli

Calculating System Velocities Using LAMMPS


For the water research I've been doing, it is useful to get the velocity autocorrelation function, which gives the density of states of the system. Here is how I ended up doing it:

One of the things that always trips me up in LAMMPS is the difference between using variables created by the user (e.g. vel_x above) and using variables LAMMPS provides (e.g. step.) When using them in, for example, a fix print, user-created variables must be wrapped in curly brackets, while the LAMMPS-provided variables must be wrapped in parens.