X-ray diffraction and Raman spectroscopy studies of temperature and composition induced phase transitions in Ba2-xSrxMgTeO6 (0 <= x <= 2)

• X-ray diffraction and Raman spectroscopy studies of Sr-substituted double perovskite compounds Ba2-xSrxMgTeO6 with (0 <= x <= 2) were carried out. At room temperature, both Rietveld refinements and Raman studies showed that two phase transitions occurred as a function of increased strontium content; from cubic to tetragonal structure, at x similar to 1.5(1), and from the tetragonal to monoclinic structure at x similar to 1.9(1). Furthermore, upon temperature increase up to 430 degrees C, the monoclinic and tetragonal perovskites manifest transformations to the tetragonal and cubic symmetries, and to the cubic symmetry, respectively. For this series, the transitions show considerable changes in the compositional and temperature dependencies of the modes, the spectral positions of which exhibit a linear behavior. The symmetry transformations between the encountered three crystal systems is revealed by significant changes of the slopes. (C) 2014 Elsevier B. V. All rights reserved.

Ämnesord

NATURVETENSKAP  -- Geovetenskap och miljövetenskap (hsv//swe)

NATURAL SCIENCES  -- Earth and Related Environmental Sciences (hsv//eng)

NATURVETENSKAP  -- Geovetenskap och miljövetenskap -- Multidisciplinär geovetenskap (hsv//swe)

NATURAL SCIENCES  -- Earth and Related Environmental Sciences -- Geosciences, Multidisciplinary (hsv//eng)

Nyckelord

Ba2-xSrxMgTeO6 double perovskite oxides

Phase transition

X-ray diffraction

Rietveld refinements

High temperature

Raman spectroscopy

Earth Science with specialization in Mineral Chemistry, Petrology and Tectonics

Geovetenskap med inriktning mot mineralogi, petrologi och tektonik

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)