Ferroelectric phases in the polytypes of TlInS₂ ternary compound

Abstract

The measurements of the real part of the dielectric constant and X‐ray diffraction studies of different polytypes of TlInS2 crystals are presented in the temperature range T = 160–250 K. Substantial influence polytypism on the occurrence of a polarized state in TlInS2 crystals has been revealed. It is shown that phase transition in 2C‐polytype, unlike C‐polytype, is not accompanied by a quadrupling of elementary cell along C axes, it is characterized by the other order parameter and occurs at higher temperatures.(© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Faraday effect in TlIn(S1�xSex)2 solid solutions (x = 0, 0.02, 0.06, 0.10, 0.15 and 0.25)

“…At cooling, the crystal undergoes a phase transition into a ferroelectric phase through an incommensurate one [2,7,8]. The main peculiarity of the phase transitions in TlInS 2 is that different polytypes can coexist in a crystalline matrix [9,10], which are characterized by different lattice parameters c. This parameter can be equal to c = 2c*, 4c*, 8c* and 16c* for different polytypes, with c* = 15.18 Å.…”