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Updated: May 19, 2026
Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Site occupancy and magnetic properties of pyrochlore-structured AgOs2O6
1Center for Condensed Matter Sciences, National Taiwan University, Taipei 10617, Taiwan.
Abstract:
AgOs(2)O(6) prepared from ion-exchanged superconducting β-pyrochlore KOs(2)O(6) has been shown to be non-superconducting. Synchrotron x-ray structure refinement suggests that AgOs(2)O(6) has the Ag ion mostly occupying the low-symmetry 32e site in the [Formula: see text] space group of proper occupancy, which is different from the original major occupancy at the high-symmetry 8b site for KOs(2)O(6), and similar to non-superconducting Na(1.4)Os(2)O(6)·H(2)O. Magnetic susceptibility measurements found no magnetic ordering down to ~1.7 K. The trace amount of isolated spins suggests that the Ag could be neutral and lead to a pure Os(6+) valence state of zero spin in the newly prepared AgOs(2)O(6).
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