CuMo0.9W0.1O4 phase transition with thermochromic, piezochromic, and thermosalient effects. Issue 12 (12th February 2015)

• Record Type: Journal Article
• Authors: Robertson, L.; Penin, N.; Blanco-Gutierrez, V.; Sheptyakov, D.; Demourgues, A.; Gaudon, M.
• Is Part Of: Journal of materials chemistry. Volume 3:Issue 12(2015)
• Page Start: 2918
• Page End: 2924
• Publication Date: 2015-02-12
• Subjects: Materials -- Periodicals; Chemistry, Analytic -- Periodicals; Optical materials -- Research -- Periodicals; Electronics -- Materials -- Research -- Periodicals; 543.0284
• DOI: 10.1039/c4tc02463j
• Languages: English
• ISSNs: 2050-7526

Abstract

Abstract : This study deals with the structural investigation by neutron diffraction of the CuMo0.9 W0.1 O4 compound phase transition, associated with thermochromic, piezochromic, and thermosalient effects. Abstract : AMoO4 compounds (A = Co, Mn, Fe, Ni, Cu, or Zn) exhibit a first-order phase transition associated with piezochromic and thermochromic phenomena, as demonstrated in previous studies. In this study, neutron diffraction patterns were collected for CuMo0.9 W0.1 O4 samples across the hysteresis cycle to accurately characterize the structural evolution ( i.e., cell parameters and atomic positions) versus temperature. This study provides information regarding the phase-transition origin. In accordance with the Birch–Murnaghan model, the phase transition is due to the higher compressibility coefficient, despite the presence of the shorter bonds for the high-temperature form. The cell-volume difference of 13% between the high and low temperature forms leads to additional exotic properties: the thermosalient effect ("jumping crystals") associated with a certain crystallite fracture (along the −101 plane) is shown.