Domain wall orientation memory as a result of consecutive ferroic phase transitions

It was shown that pattern of domain structure in ferroic crystals undergoin g a sequence of phase transitions, changes and depends on the phase precedi ng the phase with ferroic arrangement. Two crystals were taken into conside rations: beta-LiNH4SO4 and (NH4)(3)H(SeO4)(2) The orientation of domain wal ls, both ferroelectric and ferroelastic, is determined by random domain wal ls, which appeared in the previous phase both ferroelectric and ferroelasti c, or a regular large scale structure, which was found in the vicinity of p hase transition in beta-LiNH4SO4.