Structural Study of Partially Deuterated Glycinium Phosphite in the Paraelectric Phase

Abstract

The crystal structures of deuterated glycinium phosphite crystals with various deuterium concentrations x (0.00, 0.25, 0.50, 0.75 and 1.00) in the paraelectric phase were determined using the X-ray imaging plate diffractometer. The hydrogen bond distances increase with increasing deuterium concentration x, especially including the disordered hydrogen atom. There is a linear relation between the transition temperature T_C and the hydrogen bond distance R_O–O. The critical bond length r_c was estimated as 2.415 Å. HPO₃ tetrahedron rotates by duteration.