Ferroelectricity in betaine phosphite

Abstract

Abstract Betaine phosphite, an addition compound of the amino acid betaine and phosphorous acid, can be grown in single crystal form from aqueous solutions. Structural, optical, dielectric, and caloric data of this new material are reported. At least two phase transitions are observed in (CH3)3NCH2COO˙H3PO3. The lower one, around 216 K, leads to a ferroelectric phase with a spontaneous polarization of about 1.7 μC/cm2.