Experimental and Theoretical Studies on alfa-In2Se3 at High Pressure

[EN] alpha(R)-In2Se3 has been experimentally and theoretically studied under compression at room temperature by means of X-ray diffraction and Raman scattering measurements as well as by ab initio total-energy and lattice-dynamics calculations. Our study has confirmed the alpha (R3m) -> beta&...

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Detalles Bibliográficos
Autores: Vilaplana Cerda, Rosario Isabel|||0000-0003-0504-2157, Gallego-Parra, Samuel|||0000-0001-6516-4303, Manjón, Francisco-Javier|||0000-0002-3926-1705, Jorge-Montero, A., Rodríguez-Hernández, Plácida, Muñoz, Alfonso, Errandonea, Daniel, Segura, Alfredo
Tipo de recurso: artículo
Fecha de publicación:2018
País:España
Institución:Universitat Politècnica de València (UPV)
Repositorio:RiuNet. Repositorio Institucional de la Universitat Politécnica de Valéncia
Idioma:inglés
OAI Identifier:oai:riunet.upv.es:10251/111627
Acceso en línea:https://riunet.upv.es/handle/10251/111627
Access Level:acceso abierto
Palabra clave:Indium selenide
High-pressure
Raman
Ab initio
X-ray diffraction
Phase transition
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Descripción
Sumario:[EN] alpha(R)-In2Se3 has been experimentally and theoretically studied under compression at room temperature by means of X-ray diffraction and Raman scattering measurements as well as by ab initio total-energy and lattice-dynamics calculations. Our study has confirmed the alpha (R3m) -> beta' (C2/m) ? beta (R (3) over barm) sequence of pressure-induced phase transitions and has allowed us to understand the mechanism of the monoclinic C2/m to rhombohedral R (3) over barm phase transition. The monoclinic C2/m phase enhances its symmetry gradually until a complete transformation to the rhombohedral R (3) over barm structure is attained above 10-12 GPa. The second-order character of this transition is the reason for the discordance in previous measurements. The comparison of Raman measurements and lattice-dynamics calculations has allowed us to tentatively assign most of the Raman-active modes of the three phases. The comparison of experimental results and simulations has helped to distinguish between the different phases of In2Se3 and resolve current controversies.