# Energy unit in real unit.

Hello LAMMPS users.

I have a question about energy unit in real unit.

I use real unit. So I think that energy unit is kcal/mol.
LAMMPS outputs step, total energy, potential energy, kinetic energy and temperature to a log file.
I think that energy unit is not kcal/mol.
I calculated the temperature assuming that the unit of kinetic energy is kcal/mol.
Then I got the value of the output temperature multiplied by the number of particles.

For example,
I use unit real.
The number of particle is 2384.
Kinetic energy is 612.34161.
I calculated the temperature as below.
Temperature[K]
=(2*612.34161[kcal/mol] * 4184[J/kcal]*2384[atoms]/(6.02214*10^23[atoms]))/(3*(1.38065*10^-23)[J/K]*2384[atoms]
=2.05428*10^5[K]
Temperature output in log file is 86.205589[K].
The temperature I calculated is about 2384 times the temperature output in log file.
So I think that energy unit in log file in real unit is kcal/mol*atoms.
Is it correct?

Please tell me about energy unit in real unit.

Tsutsumi Yuuta

Mail:[email protected]

please see the documentation of the “units” command.

axel.