Title:
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X-ray diffraction, thermal analysis, and Raman scattering study of K2BeF4 and comparation to other member of the (beta)-K2SO4 family with ferroelectric -paraelectric transition
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Author:
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Solans, Xavier, 1949-2007; González-Silgo, C.; Calvet Pallàs, Maria Teresa; Ruiz-Pérez, C.; Martínez Sarrión, María Luisa; Mestres i Vila, Ma. Lourdes
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Other authors:
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Universitat de Barcelona |
Abstract:
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Thermal analysis, powder diffraction, and Raman scattering as a function of the temperature were carried out on K2BeF4. Moreover, the crystal structure was determined at 293 K from powder diffraction. The compound shows a transition from Pna21 to Pnam space group at 921 K with a transition enthalpy of 5 kJ/mol. The transition is assumed to be first order because the compound shows metastability. Structurally and spectroscopically the transition is similar to those observed in (NH4)2SO4, which suggests that the low-temperature phase is ferroelectric. In order to confirm it, the spontaneous polarization has been computed using an ionic model. |
Subject(s):
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-Difracció -Ferroelectricitat -Dielèctrics -Diffraction -Ferroelectricity -Dielectrics |
Rights:
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(c) The American Physical Society, 1998
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Document type:
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Article Article - Published version |
Published by:
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The American Physical Society
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