System of polymorphic transformations of structural types of compounds of ABX4 composition

An investigation of the types of structures of ABX4 compositions has shown them to comprise three main structural types-CaWO4, TiO2 and MgWO4- that are active in polymorphic transition patterns. Considered is the variation of the coordination of cations during the motion along the branches of the polymorphic transformation patterns and the interrelations between the ircomponent structures. It is found that the main types of transformations are deformation and ordering. The resultant pattern has been compared to similar patterns corresponding to Asub(x)Bsub(y) compositionss