Journal article
Pressure dependence of the crystal structure of SrCeO3 perovskite
The crystal structure of SrCeO3 perovskite, orthorhombic, space group Pmcn, has been determined from Rietveld profile refinement of neutron, time-of-flight, powder diffraction data at four pressures between 0 and 7.9GPa. The unit cell compression behaviour is anisotropic with κa=3.14(8)×10−3GPa−1, κb=3.18(8)×10−3GPa−1 and κc=1.78(6)×10−3GPa−1, and fitting the pressure dependence of the unit cell volume using a second-order Birch–Murnaghan equation of state, the bulk modulus has been determined as 110.1(6)GPa.
Contrary to a model based on EXAFS results, which predicts octahedral tilting as the dominant compression mechanism in perovskites with excess A-site volume, SrCeO3 undergoes bond compression with increasing pressure in agreement with the results obtained in a recent Raman investigation. SrCeO3 behaves atypically when compared to other AIIBIVO3 perovskites in both temperature and pressure, which is attributed to the magnitude of the CeO bond length.
Language: | English |
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Year: | 2005 |
Pages: | 131-137 |
ISSN: | 18734669 and 09258388 |
Types: | Journal article |
DOI: | 10.1016/j.jallcom.2004.11.020 |
ORCIDs: | Bonanos, N. |