Protic ionic liquids (PILs) are an interesting sub-class of room temperature ionic liquids. They differ from conventional, a protic ionic liquids, because of the major role played by hydrogen bonding in influencing their properties, from structure, to dynamics and thermodynamics. For example ethylammonium nitrate (EAN), a model PIL, has a structure that is profoundly affected by hydrogen bonding, being, in many respects, very similar to water. On the other hand what makes PILs very peculiar is the coexistence of H-bonding interactions, strong coulombic ones, as well as dispersive ones: in other words, much of the properties of this material are influenced by its amphiphilic behaviour. For this reason the exploration of the structural implications in EAN/methanol of the coupling between coulombic and dispersive interactions is expected to be very instructive.