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Updated: Apr 14, 2026

Comparison of Two Different Synthesis Methods of Single Crystals of Superconducting Uranium Ditelluride
Published on: July 8, 2021
Flux Crystal Growth and Optical Properties of Two Uranium-Containing Silicates: A2USiO6 (A = Cs, Rb)
Cory Michael Read1, Mark D Smith1, Ray Withers2
1†Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208, United States.
Abstract:
Single crystals of two uranium silicates, Cs2USiO6 and Rb2USiO6, have been grown from molten fluoride fluxes and structurally characterized by single-crystal X-ray diffraction. Cs2USiO6 crystallizes in the body-centered orthorhombic space group, Immm, with a = 8.5812(4) Å, b = 13.0011(6) Å, and c = 13.8811(7) Å. The size of Rb is slightly too small to fit into this structural framework without effecting slight structural changes that result in a 6-fold superstructure. Sharp satellite peaks were observed in the single-crystal X-ray diffraction data, indicating the existing of a superstructure. The crystals were examined by electron diffraction, the results of which suggest that the structure can be thought of as the Immm isotype (a = 8.4916(6) Å, b = 12.6678(9) Å, and c = 13.5077(9) Å) on average, with an approximately 6-fold superstructure along the c axis. The materials were further characterized by UV-vis reflectance spectroscopy.
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