A complex study of domain structure of CsDSO4 crystals has been performed o
ver a wide temperature range. The effect of internal and external stresses
and the PO4 impurity on the kinetics of domain growth is considered. The be
havior of the domain structure of the CsDSO4 crystals is compared with mart
ensite phase transformations. A model of crystal-lattice transformations in
various phases is suggested, including an intermediate phase with the unkn
own symmetry of CsDSO4 crystals. (C) 2001 MAIK "Nauka/Interpetiodica".