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arXiv · 1205.1077

Pressure-induced symmetry breaking in tetragonal CsAuI3

Shibing Wang·Shigeto Hirai·Maxwell C. Shapiro·Scott C. Riggs·Theodore H. Geballe·Wendy L. Mao·Ian R. Fisher
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Abstract

Results of in situ high pressure x-ray powder diffraction on the mixed valence compound Cs2Au(I)Au(III)I6 (CsAuI3) are reported, for pressures up to 21 GPa in a diamond anvil cell under hydrostatic conditions. We find a reversible pressure-induced tetragonal to orthorhombic structural transition at 5.5-6 GPa, and reversible amorphization at 12-14 GPa. Two alternative structures are proposed for the high-pressure orthorhombic phase, and are discussed in the context of a possible Au valence transition.

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Shibing Wang, Shigeto Hirai, Maxwell C. Shapiro, Scott C. Riggs, Theodore H. Geballe, Wendy L. Mao, Ian R. Fisher. 2012-10-24. Pressure-induced symmetry breaking in tetragonal CsAuI3. https://doi.org/10.1103/physrevb.87.054104

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