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Updated: Nov 30, 2025
Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Crystal Structures, Superconducting Properties, and the Coloring Problem in ReAlSi and ReGaSi
Victoria Decocq1, Xin Gui2, Alec Neeson1
1Department of Chemistry, Missouri State University, Springfield, Missouri 65897, United States.
Abstract:
The only nonsuperconducting rhenium-silicon binary compound, ReSi1.75, was heavily p-doped with Ga and Al into ReGaSi and ReAlSi in an attempt to evoke superconductivity. They were synthesized and their crystal structures were studied by both X-ray and neutron diffraction. Si and Ga/Al atoms are ordered into alternating layers, which was rationalized with the "coloring problem" study via first-principles calculations. ReGaSi cannot be further p-doped with more Ga, but ReAlSi can be doped with more Al to ReAl1.2Si0.8, in which Si and Al atoms are not ordered but randomly distributed on the same sites. The superconductivity measurements over these compounds demonstrate that the ordered ReAlSi and ReGaSi are not bulk superconductors. However, ReAl1.2Si0.8 becomes bulk superconductor with Tc = ∼3.5 K, which has been confirmed by magnetism, resistivity, and specific heat measurements.
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