Linear Thermal Expansion of Ferroelectric Deuterated Triglycine Sulphate

Thermal dilatation experiments are performed for partially deuterated triglycine sulphate crystals and the temperature dependence of linear expansion coefficients is studied in the temperature range 77–420 K for the three principal directions. The critical behavior of the crystal due to ferroelectric phase transition is shown to be well described within the first fluctuation correction approach.