I think there might be an error in the docs. The units doc
page says, "For the definition of Kcal in real units, LAMMPS
uses the thermochemical calorie = 4.184 J."
It seems that the definition in lammps is 1 KCal = 4184 J for
You can test it with a minimization using LJ/Cut comparing real
and metal units (see attached). The pressure of the minimized
geometry is the same only when 1 KCal = 4184 J. This conversion
also shows up in the argon heat/flux example.
metal.in (726 Bytes)
metal.out (2.45 KB)
real.in (523 Bytes)
real.out (1.87 KB)
wrong.in (760 Bytes)
wrong.out (2.54 KB)