# Interacting particles

We are familiar with the grand partition function for the grand canonical ensemble. This makes me wonder: what kinds of modifications would be required if the particles interacted?

Thanks.

-

None. The grand canonical partition function is $$Z_\mathrm{GC} = \mathrm{tr}(e^{-\beta (H - \mu N)})$$ where $H$ is the hamiltonian and $N$ is the number operator.
Why in a box? Do you mean interaction with walls via $L$-dependence of energies? –  Vladimir Kalitvianski Mar 26 '13 at 20:37