1998/02/16 by K. Rotereau, Ph. Daniel, A Désert +1 · 2 citations
Chemistry · Materials Science · #Inorganic Fluorides and Related Compounds #Crystal Structures and Properties #Solid-state spectroscopy and crystallography
paper · doi:10.1088/0953-8984/10/6/026
openalex publication_date 1998/02/16 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/30
(samarium fluoride) exhibits orthorhombic symmetry (space group Pnma ; type) at room temperature and rhombohedral symmetry (space group type) at high temperature. In this paper we describe a study of the structural phase transition mechanism occurring in this compound performed by means of differential thermal analysis, x-ray diffraction and Raman scattering. The transition temperature was determined to be and the first-order character of the orthorhombic-rhombohedral phase transition was confirmed. The crystal structure of was refined in the two phases using a Rietveld powder diffraction method. The correlation between the coordination polyhedra appropriate to the two structure types has been established and a proposed transition mechanism is described in this paper. Moreover, a full vibrational investigation of both phases of is presented together with a group theory analysis.