YbGaGe

YbGaGe
Names
Other names
Ytterbium Gallium Germanium
Identifiers
3D model (JSmol)
  • 1:1:1: InChI=1S/Ga.Ge.Yb
  • 1:1:1: [Ga].[Ge].[Yb]
Structure
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).

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. Such materials have applications in space and other environments where low thermal expansion materials are required. However, subsequent measurements by other groups were not able to reproduce those results, but rather found expansion coefficients similar to copper.

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.

References

  1. 1 2 Salvador, James R; Guo, Fu; Hogan, Tim; Kanatzidis, Mercouri G (2003). "Zero thermal expansion in YbGa Ge due to an electronic valence transition". Nature. 425 (6959): 702–705. Bibcode:2003Natur.425..702S. doi:10.1038/nature02011. PMID 14562099. S2CID 4412282.
  2. ↑ "Zero Expansion Conductor". October 20, 2003. p. 1. Retrieved May 23, 2011.
  3. ↑ Janssen, Y; Chang, S; Cho, B. K; Llobet, A; Dennis, K. W; McCallum, R. W; Mc Queeney, R. J; Canfield, P. C (2004). "YbGaGe: Normal thermal expansion". arXiv:cond-mat/0407683.
  4. ↑ Booth, C. H; Christianson, A. D; Lawrence, J. M; Pham, L. D; Lashley, J. C; Drymiotis, F. R (2007). "Ytterbium divalency and lattice disorder in near-zero thermal expansion YbGaGe". Physical Review B. 75 (1) 012301. arXiv:cond-mat/0611166. Bibcode:2007PhRvB..75a2301B. doi:10.1103/PhysRevB.75.012301. S2CID 94678137.