The lack of significant interactions between the NH4 + cations in the same channel likely plays a significant role in the relatively low barrier to reorientation, as there is no strong restriction preventing neighbouring molecular cations from adopting different orientations. Previous EPR work suggested this transition belongs to a 2D universality class; this is probably associated with ordering of the crystallographically distinct channels within the ab plane while lone NH4 + cations within a channel may flip their orientations. The observed crystallographic disorder of the NH4 + molecules containing N2 in both phases potentially reflects a greater tendency to rotation. Ultimately our proposition is that there is a link between the disorder in the orientation of the NH4 + cations and their dielectric relaxation. That orientational disorder is responsible for their relaxor-like dielectric relaxation is similar to [NH3NH2]Mg(HCO2)3 , despite a number of differences between the reported origins of their ferroelectric polarisation and phase transitions.