Maximum valency lattice gas models

We study lattice gas models with the imposition of a constraint on the maximum number of bonds (nearest-neighbour interactions) that particles can participate in. The critical parameters, as well as the coexistence region, are studied using the mean field approximation and the Bethe-Peierls approximation. We find that the reduction of the number of interactions suppresses the temperature-density region where the liquid and gas phases coexist. We confirm these results from simulations using the histogram reweighting method employing grand canonical Monte Carlo simulations.