Critical Behavior of a Fluid in a Disordered Porous Matrix: An Ornstein-Zernike Approach

Using a liquid-state approach based on Ornstein-Zernike equations, we study the behavior of a fluid inside a porous disordered matrix near the liquid-gas critical point. The results obtained within various standard approximation schemes such as lowest-order $\gamma$ ordering and the mean-spherical approximation suggest that the critical behavior is closely related to that of the random-field Ising model.