Dielectric relaxation and spontaneous polarization studies have been carried out in a low molar mass organosiloxane liquid crystal, TSi10PPBN4 which displays a wide temperature range of de Vries Smectic A* and chiral Smectic C* phases. The temperature variation of the permittivity and dielectric loss studied are found to have anomalous variations in the vicinity of the phase transitions. The frequency variation of permittivity and dielectric loss are also studied in the de Vries Smectic A* and Smectic C* phases. The relaxation frequency, fR is found to decrease with decreasing temperature. Temperature variation of fR is found to follow an Arrhenius shift from which the activation energy is estimated. The thermal variation of the spontaneous polarization, Ps is measured using the polarization reversal technique in the Smectic C* phase. Ps increases initially, reaches a peak value and then drops drastically in the vicinity of the SmC*-SmA*de Vries phase transition.
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机译：在低摩尔质量的有机硅氧烷液晶TSi10PPBN4中进行了介电弛豫和自发极化研究，该液晶显示了de Vries Smectic A *和手性Smectic C *相的宽温度范围。发现所研究的介电常数和介电损耗的温度变化在相变附近具有异常变化。还研究了de Vries Smectic A *和Smectic C *相的介电常数和介电损耗的频率变化。发现松弛频率fR随着温度降低而降低。发现fR的温度变化遵循Arrhenius位移，据此可以估算活化能。自发极化Ps的热变化是通过在Smectic C *相中使用极化反转技术来测量的。 Ps最初增加，达到峰值，然后在SmC * -SmA * de Vries相变附近急剧下降。
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