Thermal Motion in Sodium Nitrite: The Temperature Dependence of Debye-Waller Factors

• Published in: Ferroelectrics Vol. 269; no. 1; pp. 321 - 326
• Main Authors: Kawamura, Y., Nitta, N., Kasano, H., Mashiyama, H.
• 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; Debye-Waller Factor; Dielectric, piezoelectric, ferroelectric and antiferroelectric materials; Dielectrics, piezoelectrics, and ferroelectrics and their properties; Exact sciences and technology; Ferroelectricity and antiferroelectricity; Least Squares Calculation; Maximum Entropy Method; Order-disorder/displacive Type; Phase transitions and curie point; Physics; Sodium Nitrite; Structure Analysis; Temperature dependence; Order-disorder transformations; Maximum entropy methods; Phase transformations; XRD; Monocrystals; Sodium nitrites; Ordered systems; Ferroelectric materials; Anomaly; Least square fit; Debye-Waller factor; Spontaneous polarization
• ISSN: 0015-0193; 1563-5112
• DOI: 10.1080/00150190211146

In order to understand the relation between the transition mechanism and the thermal vibration, the temperature dependence of the Debye-Waller factor is investigated in NaNO 2 by single-crystal X-ray diffractometry. The crystal parameters are refined by least squares calculations both in paraelectric and ferroelectric phases. The maximum entropy method is also employed to estimate the spontaneous polarization. The Debye-Waller factor displays a minor anomaly at the order-disorder transition point. The result is compared with K 2 SeO 4 , a typical displacive crystal.