Effects of translational symmetry breaking induced by the boundaries in a driven diffusive system

We study the effects of the boundary conditions in a driven diffusive lattice-gas model which is known to display kinetic phase transitions. We find, in the case of attractive interaction, that a boundary-condition-induced symmetry breaking of the translational invariance, along the direction of the external field, destroys the second-order kinetic phase transition. This feature is absent in equilibrium systems. In the repulsive case, the phase diagram and critical properties are probably unaltered.