The phase transition of glycine phosphite (GPI) and partially deuterated glycine phosphite (DGPI) single crystals has been characterized by applying the effective mean field theory. Temperature dependence of the spontaneous polarization P s(T) has been analyzed from hysteresis loops for these crystals. With the increment of deuteration ratio, saturated spontaneous polarization P s 0 is also increased. As a result, the quantitative phase transition indicator g according to the mean field theory is being increased but the maximum increment is underlying the decisive tricritical point g = 1/3. The phase transition character of GPI crystal is proved to be second order but very near to the tricritical point.

The phase transition character of glycine phosphite crystals is second order, near the tricritical point, with a maximum increment at g = 1/3.

Ferroelectric Phase Transition Character of Glycine Phosphite

Key Takeaway: The phase transition character of glycine phosphite crystals is second order, near the tricritical point, with a maximum increment at g = 1/3.