Symmetry mode analysis of the phase transitions in Rb.sub.2./sub.ZnBr.sub.4./sub..

0366892 - FZÚ 2012 RIV DE eng J - Journal Article
Zúniga, F. J. - Perez-Mato, J. M. - Orobengoa, D. - Petříček, Václav - Breczewski, T.
Symmetry mode analysis of the phase transitions in Rb₂ZnBr₄.
Zeitschrift für Kristallographie. Roč. 226, č. 5 (2010), s. 454-466. ISSN 0044-2968
Grant - others:AV ČR(CZ) AP0701
Program: Akademická prémie - Praemium Academiae
Institutional research plan: CEZ:AV0Z10100521
Keywords : structure analysis * symmetry-adapted modes * structure refinement
Subject RIV: BM - Solid Matter Physics ; Magnetism
Impact factor: 1.155, year: 2010

Crystal structures of low temperature phases III, IV and V of rubidium zinc bromide have been determined by single crystal X-ray diffraction at 90 K, 85 K, and 30 K, respectively. The analysis of the structures in terms of symmetry-adapted modes of the high temperature prototype phase permits the identification of the modes responsible for each phase and to assess its thermal evolution. The primary mode responsible for the incommensurate and lock-in phases remains dominant throughout the whole transition sequence, maintaining its structure and slightly increasing its amplitude as tempera! ture decreases. The two monoclinic phases IV and V are presumably due to the instability of a second mode associated with a single active irreducible representation.
Permanent Link: http://hdl.handle.net/11104/0201727