Heat capacity calculations in the NVT ensemble

Dear all,

I am currently trying to calculate the heat capacity of a system by evaluating the fluctuations of energy during NVT simulations.

The system considered is a periodic box filled with amorphous silicon (actually two samples, obtained from quenching from the melt, and from random distribution + annealing). In order to compare the results, I also run a similar simulation on the same box filled with crystalline silicon.

This is the parameters file I have set up for the simulation of the crystalline sample :