کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1403975 | 1501843 | 2010 | 5 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: High temperature Raman spectroscopy studies of the phase transitions in Sr2NiWO6 and Sr2MgWO6 double perovskite oxides High temperature Raman spectroscopy studies of the phase transitions in Sr2NiWO6 and Sr2MgWO6 double perovskite oxides](/preview/png/1403975.png)
In this paper, we report on high temperature Raman spectroscopy studies (up to 550 °C) of the phase transitions in Sr2BWO6 (B = Ni, Mg) double perovskite oxides. For both compounds, the transition from the tetragonal (I4/m) phase to the cubic (Fm-3m) phase is accompanied by considerable changes in the temperature dependence of the modes. To better view this phase transition, the FWHM temperature dependence of the most intense modes were studied; by this study, we have obtained a sensitive guide to the onset of the phase transition. A large increase of the FWHM with increasing temperature is observed for all modes in the spectrum, clear transitional effects were observed: the width behaves in a linear way as a function of temperature; when the temperature reached around 300 °C, a drop in the width of this mode was observed; thus, showing the phase transition occurrence for both compounds. This drop is much more illustrated in Ni-containing compound than in Sr2MgWO6.
Journal: Journal of Molecular Structure - Volume 971, Issues 1–3, 5 May 2010, Pages 18–22