[lammps-users] Specific heat calculation

I am trying to calculate specific heat of the silicon. As far as I understand it is possible to determine it from the plot of Enthalpy against Temperature. The slope coefficient will show this specific heat. I am researching silicon, I used NPT ensemble with 30000 atoms. The slope was equal to 28 Kcal/(mol*K), which is clearly too large. Any ideas about such effect ?

Try calculating it through energy fluctuations at certain temperature as well. See if you are seeing same numbers. If true, it could be issue with the force field. If not, you might wanna think more about why it is happening?

This is well known, see e.g. J. Chem. Phys. 113 (2000) 2976 and references in this paper.

Z. Insepov