Structures within the (Formula presented) system (Formula presented) were refined by Rietveld analysis of powder x-ray-diffraction data. Our results reveal three distinct regimes that parallel energetic transformations within the series. For (Formula presented) enthalpies of oxidation are strongly exothermic and the compounds are monophasic and orthorhombic. Hole saturation occurs for (Formula presented) and the symmetry decreases from orthorhombic to monoclinic. For (Formula presented) diffraction patterns suggest phase immiscibility between a Sr-poor, hole-saturated compound and a Sr-rich phase for which oxidation is strongly favored. Fourier synthesis maps for all compositions revealed evidence for microtwinning and positional disorder among apical oxygen atoms.
|Original language||English (US)|
|Number of pages||9|
|Journal||Physical Review B - Condensed Matter and Materials Physics|
|State||Published - 1998|
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics