Ukrainian Journal of Physical Optics 

The domain structure of the Rb₂Cd₂(SO₄)₃ and Tl₂Cd₂(SO₄)₃ langbeinite crystals 
  2. The domain structure in the ferroelectric-ferroelastic phases of the Rb₂Cd₂(SO₄)₃ crystals

Vlokh R., Skab I., Girnyk I., Czapla Z., Dacko S., Kosturek B.

The temperature behavior of the domain structure in the ferroelectric-ferroelastic phases of the Rb₂Cd₂(SO₄)₃ langbeinite crystals were investigated by the optical microscopy method. The new phase with the point group of symmetry 3 was found in the temperature region 130K<T<113K. By the observation of the domain structure in the temperature region 113K<T<101K the coexistence of the monoclinic and trigonal phase was revealed. The broad maximum of the dielectric permitivity measured at frequency 1MHz around T=T_c4=113K was found. This maximum significate that phase transition at T_c4 is the diffuse phase transition

Key words: Rb₂Cd₂(SO₄)₃ , langbeinite crystals, domain structure, dielectric permitivity, phase transition

doi 10.3116/16091833/1/2/103/2000

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