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DOE OSTI · 1816534

Lattice Dynamics and Structural Phase Transitions in Eu 2 O 3

Łażewski, Jan·Sternik, Małgorzata·Jochym, Paweł T.·Kalt, Jochen·Stankov, Svetoslav·Chumakov, Aleksandr I.·Göttlicher, Jorg·Rüffer, Rudolf·Baumbach, Tilo·Piekarz, Przemysław
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Abstract

Using the density functional theory, we study the structural and lattice dynamical properties of europium sesquioxide (Eu 2 O 3 ) in the cubic, trigonal, and monoclinic phases. The obtained lattice parameters and energies of the Raman modes show a good agreement with the available experimental data. The Eu-partial phonon density of states calculated for the cubic structure is compared with the nuclear inelastic scattering data obtained from a 20 nm thick Eu 2 O 3 film deposited on a YSZ substrate. A small shift of the experimental spectrum to higher energies results from a compressive strain induced by the substrate. On the basis of lattice and phonon properties, we analyze the mechanisms of structural transitions between different phases of Eu 2 O 3 .

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRYChemical structureCrystal structureEnergyPhase transitionsPhonons

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Łażewski, Jan, Sternik, Małgorzata, Jochym, Paweł T., Kalt, Jochen, Stankov, Svetoslav, Chumakov, Aleksandr I., Göttlicher, Jorg, Rüffer, Rudolf, Baumbach, Tilo, Piekarz, Przemysław. 2021-06-18. Lattice Dynamics and Structural Phase Transitions in Eu 2 O 3. https://doi.org/10.1021/acs.inorgchem.1c00708

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