Crossover in the pressure evolution of elementary distortions in RFeO3 perovskites and its impact on their phase transition

• Tipo: Artigo em Revista Científica Internacional
• Data: 2019

Autores

Vilarinho, R (Autor) Outra; Bouvier, P (Autor) Outra; Guennou, M (Autor) Outra; Peral, I (Autor) Outra; Weber, MC (Autor) Outra; Tavares, P (Autor) Outra; Mihalik, M (Autor) Outra; Mihalik, M (Autor) Outra; Garbarino, G (Autor) Outra; Mezouar, M (Autor) Outra; Kreisel, J (Autor) Outra; Almeida, A (Autor) FCUP; Agostinho Moreira, JA (Autor) FCUP

Revista

Título: Physical Review B

Vol. 99

ISSN: 2469-9950

Editora: American Physical Society

Indexação

ISI Web of Knowledge - 18 Citações

Scopus - 18 Citações

Outras Informações

ID Authenticus: P-00Q-9QP

DOI: 10.1103/physrevb.99.064109

Abstract (EN): This work reports on the pressure dependence of the octahedral tilts and mean Fe-O bond lengths in RFeO3 (R = Nd, Sm, Eu, Gd, Tb, and Dy), determined through synchrotron x-ray diffraction and Raman scattering, and their role on the pressure-induced phase transition displayed by all of these compounds. For larger rare-earth cations (Nd-Sm), both anti- and in-phase octahedral tilting decrease as pressure increases, whereas the reverse behavior is observed for smaller ones (Gd-Dy). EuFeO3 stands at the borderline, with nearly pressure-independent tilt angles. For the compounds where the tilts increase with pressure, the FeO6 octahedra are compressed at lower rates than for those ones exhibiting opposite pressure tilt dependence. The crossover between the two opposite pressure behaviors is discussed in relation to the general rules proposed from different theoretical approaches. The similarity of the pressure-induced isostructural insulator-to-metal phase transition, observed in the whole series, points out that the tilts play a minor role in its driving mechanisms. A clear relationship between octahedral compressibility and critical pressure is ascertained.

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 10