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arXiv · 1111.7017

Single crystal growth by self-flux method of the mixed valence gold halides Cs$_2$[Au$^{I}$X$_2$][Au$^{III}$X$_4$] (X=Br,I)

Scott C. Riggs·M. C. Shapiro·F. Corredor·T. H. Geballe·I. R. Fisher·Gregory T. McCandless·Julia Y. Chan
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Abstract

High quality single crystals of Cs$_2$Au$_2$X$_6$ (X=Br,I) were grown using a ternary self-flux method. Structural refinements based on single crystal X-ray diffraction measurements show that both materials have a distorted perovskite structure belonging to the I4/mmm space group with full site occupancy. Transport measurements reveal a large bandgap of 550 $\pm$ 100 meV for Cs$_2$Au$_2$I$_6$ and 520 $\pm$ 80 meV for Cs$_2$Au$_2$Br$_6$. Initial attempts at chemical substitution are described.

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Scott C. Riggs, M. C. Shapiro, F. Corredor, T. H. Geballe, I. R. Fisher, Gregory T. McCandless, Julia Y. Chan. 2011-11-29. Single crystal growth by self-flux method of the mixed valence gold halides Cs$_2$[Au$^{I}$X$_2$][Au$^{III}$X$_4$] (X=Br,I). https://doi.org/10.1016/j.jcrysgro.2012.06.039

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