A simple equation of state is derived for a hard-core lattice gas of side length λ, and compared to the results of Monte Carlo simulations. In the disordered fluid phase, the equation is found to work very well for a two-dimensional lattice gas of hard squares and reasonably well for the three-dimensional gas of hard cubes.
Physical review. E, Statistical, nonlinear, and soft matter physics. Vol. 75, no. 5 (May 2007), 052101, 3 p.