Ferroic crystals and tensor distinction

The tensor distinction of ferroic crystals by physical property tensors is reviewed. We consider whether or not a physical property can simultaneously distinguish among all the domains which arise in a ferroic phase transition and between pairs of domains. Because of their central role in determining switching of domains, we also consider which components of a tensor distinguish between the pairs of domains. We also include the fourth primary ferroic physical property, the toroidal moment, in addition to magnetization, polarization, and strain.