The role of π-bonding on the high temperature structures in the uranium double perovskites Ba2CaUO6 and BaSrCaUO6
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Date
2015-08-12
Journal Title
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Publisher
Royal Society of Chemistry
Abstract
The high temperature structural behaviour of the uranium perovskites Ba2CaUO6 and BaSrCaUO6 has been investigated using a combination of synchrotron X-ray and neutron powder diffraction. Ba2CaUO6 undergoes a complex sequence of structures associated with the progressive loss of cooperative octahedral tilting: P21/n → I2/m → I2/m → I4/m → Fm[3 with combining macron]m. The observation of the intermediate tetragonal structure, I4/m, in this, contrasts with the previously reported rhombohedral R[3 with combining macron] intermediate formed by the Ba2SrUO6 oxide. The importance of π-bonding in determining the structural sequence is discussed. © The Royal Society of Chemistry 2015
Description
Keywords
Temperature range 0400-1000 K, Uranium, Perovskites, X-ray diffraction, Neutron diffraction, Oxides
Citation
Reynolds, E., Thorogood, G. J., Avdeev, M., Brand, H. E. A., Gu, Q., & Kennedy, B. J. (2015). The role of π-bonding on the high temperature structures in the uranium double perovskites Ba2CaUO6 and BaSrCaUO6. Dalton Transactions, 44(36), 16036-16044. doi:10.1039/C5DT02663F