The low frequency dielectric constant measurements in MASD (Methylammonium Aluminum Sulphate Dodecahydrate) indicate a second order ferro to paraelectric transition. Additional transitions are also indicated at about 145°K and 153°K by very small anomalies in the dielectric constant measurements. The thickness dependent dielectric measurements suggest the formation of a single homogeneous surface layer and the surface capacitance seems to be independent of temperature. Dielectric dispersion (in the frequency range 30–100 KHz) has been observed in the ferroelectric phase and can be attributed to domain wall motions.

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