YbGaGe
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| Names | |
|---|---|
| Other names
Ytterbium Gallium Germanium | |
| Identifiers | |
3D model (JSmol) |
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| Structure[1] | |
| MoC2 structure type | |
| P63/mmc (No. 194) | |
a = 420.56 pm, c = 1678.1 pm | |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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YbGaGe is an alloy of ytterbium, gallium and germanium. It sparked interest because one group of researchers reported that it exhibits zero thermal expansion, while being conductive.[1] Such materials have applications in space and other environments where low thermal expansion materials are required.[2] However, subsequent measurements by other groups were not able to reproduce those results, but rather found expansion coefficients similar to copper.[3]
Nevertheless, YbGaGe does show anomalous thermal expansion. Near-zero thermal expansion was observed by Booth et al. It was found that near-zero thermal expansion (NZTE) in YbGaGe is sensitive to stoichiometry and defect concentration. However, the near-zero thermal expansion mechanism remains elusive.[4]