Generalized depletion potentials

We propose that the behaviour of asymmetric binary fluid mixtures with a large class of attractive or repulsive interparticle interactions can be understood by mapping onto effective non-additive hard-sphere models. The latter are best analysed in terms of their underlying depletion potentials which can be exactly scaled onto known additive ones. By tuning the non-additivity, a wide variety of attractive or repulsive generalized depletion potential shapes and associated phase behaviour can be 'engineered', leading, for example, to two ways to stabilize colloidal suspensions by adding smaller particles.