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Landau theory applied to phase transitions in calcium orthotungstate and isostructural compounds

D. Errandonea
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Abstract

The pressure-driven tetragonal-to-monoclinic phase transition in CaWO4 and related scheelite-structured orthotungstates is analysed in terms of spontaneous strains. Based upon our previous high-pressure x-ray diffraction results and the Landau theory, it is suggested that the scheelite-to-fergusonite transition is of second order in nature.

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D. Errandonea. 2006-11-23. Landau theory applied to phase transitions in calcium orthotungstate and isostructural compounds. https://doi.org/10.1209/0295-5075%2F77%2F56001

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