Spontaneous Polarization In Ferroelectric Phase Research Articles

Ferroelectric Phase Transition in (CH3NH3)5Bi2Cl11-Excess Entropy and Spontaneous Birefringence

The results of precise measurements of spontaneous birefringence in the temperature range of 285 K 320 K for (CH 3 NH 3 ) 5 Bi 2 Cl 11 (PMACB) are presented. Linear dependences between the spontaneous birefringence and the spontaneous polarization in ferroelectric phase were shown in a wide temperature range. Linear relations of the spontaneous birefringence and the excess entropy for PMACB crystals were proved.