Correlation Between Cation Vacancies and Phase Transition Behavior in La-Modified Sodium Bismuth Titanate

• Published in: Ferroelectrics Vol. 270; no. 1; pp. 203 - 208
• Main Authors: Yi, Jae Yun, Lee, Jung-Kun, Hong, Kug Sun
• Format: Journal Article Conference Proceeding
• Language: English
• Published: London Taylor & Francis Group 01.01.2002; Taylor and Francis
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Dielectric properties of solids and liquids; Dielectric, piezoelectric, ferroelectric and antiferroelectric materials; Dielectrics, piezoelectrics, and ferroelectrics and their properties; Exact sciences and technology; Incommensurate; Nbt; Niobates, titanates, tantalates, pzt ceramics, etc; Permittivity (dielectric function); Phase Transition; Physics; Vacancy; Temperature dependence; Commensurate-incommensurate transformations; Inorganic compounds; Vacancies; Incommensurate phases; Phase transformations; Transition element compounds; Bismuth Titanates; Dielectric relaxation; Ferroelectric transitions; Ferroelectric materials; Sodium Titanates; Ordering; Quaternary compounds; Permittivity
• ISSN: 0015-0193; 1563-5112
• DOI: 10.1080/713716123

In this study, the influence of cation vacancy on phase transition was investigated with the aid of dielectric spectroscopy. La ions were incorporated into (NBT) to cause A site vacancy (named as NBLT-A) or B site vacancy (named as NBLT-B). In NBLT-A, La modification reduced the degree of cation ordering in A-site and caused a dielectric relaxation in a transition from ferroelectric commensurate phase to incommensurate phase. However, NBLT-B (x=0.05) shows only diffuse phase transition between paraelectric and ferroelectric phase. The phenomenon was discussed in terms of the role of A-site cation ordering and vacancies on translational symmetry of dipoles.