Low Temperature Symmetry of Pyrochlore Oxide Cd2Re2O7

Jun-Ichi Yamaura; Zenji Hiroi

doi:10.1143/jpsj.71.2598

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Low Temperature Symmetry of Pyrochlore Oxide Cd2Re2O7

Jun-Ichi Yamaura·Zenji Hiroi

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Abstract

We report the X-ray study for the pyrochlore oxide Cd2Re2O7. Two symmetry-lowering structural transitions were observed at Ts1=200K and Ts2=120K. The former is of the second order from the ideal cubic pyrochlore structure with space group Fd-3m to a tetragonally distorted structure with I-4m2, while the latter is of the first order likely to another tetragonal space group I4122. We discuss the feature of the lattice deformation.

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Jun-Ichi Yamaura, Zenji Hiroi. 2002-08-09. Low Temperature Symmetry of Pyrochlore Oxide Cd2Re2O7. https://doi.org/10.1143/jpsj.71.2598

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