Here is a description of the LAMMPS output resulting from running a perfect Au crystal calculation.
Lattice spacing in x,y,z = 4.08 4.08 4.08 Created orthogonal box = (0 0 0) to (40.8 40.8 40.8) 1 by 1 by 1 processor grid Created 4000 atoms
Again, like with GULP, make sure you see what you expect here. Are the dimensions correct? Are the expected number of atoms present?
Step Temp E_pair E_mol TotEng Press Volume 0 0 -15720 0 -15720 0.022463201 67917.312 1 0 -15720 0 -15720 0.022463201 67917.312
Here the minimizer goes to work. You see a variety of thermodynamic outputs at each step. We've created a perfect Au crystal at its equilibrium lattice constant, so nothing happens. If we make perturbations to that (a vacancy, a surface, etc.) you should see the energy drop iteratively as LAMMPS moves atoms around to relax them.
Minimization stats: Stopping criterion = energy tolerance Energy initial, next-to-last, final = -15720.0000008 -15720.0000008 -15720.0000008
The minimization is complete. LAMMPS tells us which of our criteria caused it to stop (should be energy tolerance or force tolerance; if it hits its max number of iterations, that's bad! It means it could relax further if we had let it). We also see here the final energy, the most important output of the simulation!