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1987) Equilibrium and metastable phases formed at successive ordering of Jahn-Teller distortions in Cu(H2O)6·SiF6 crystals, Ferroelectrics, 75:1, 431-447,The first-order phase transitions and dehydration in solid solutions Cu,-,Me,(H,O),~SiF, (Me = Zn, Fe, Ni) are studied at temperatures from 14 K to 300 K using the roentgenography, adiabatic calorimetry and Mossbauer spectroscopy. As temperature decreases-the identified phasqs from the sequence: dynamically disordered (R3, z = l), partially disordered (R3, z = 4), ordered (Pl, z = 2). A possibility for the existence of the Jahn-Teller glass crystalline phase (the result of the quenching of partially ordered phase at v>20K/min), its devitrification and ordering of the distortions of Jahn-Teller complexes in the phase the structure of which has not yet been determined is substantiated.It is shown that the interaction of Jahn-Teller complexes [CU(H,O),]~+ is the general mechanism of all the transformations. The role of the Jahn-Teller dynamics in phase formation is found. The results are interpreted within the framework of the four-sublattice model which is in good agreement with the experiment.

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