Chemistry:Lanthanum decahydride

From HandWiki
Lanthanum decahydride
Identifiers
3D model (JSmol)
Properties
H10La
Molar mass 148.985 g·mol−1
Structure[2]
Cubic
Fm3m
a = 5.1019(5) Å
at 150 GPa
132.80(4) Å3
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

Lanthanum decahydride is a polyhydride or superhydride compound of lanthanum and hydrogen (LaH10) that has shown promise in an experiment reported by Drozdov, Eremets et al in 2019 of being a high-temperature superconductor. It has a superconducting transition temperature TC ~ 250 K (−23 °C; −10 °F) at a pressure of 150 gigapascals (GPa), and its synthesis required pressures above ~160 GPa.[2] The possibility of the existence of the superconducting state in hydrogenated compounds was proposed by Ashcroft in 2004.[3]

Synopsis

The compound exhibits a Meissner effect below the superconducting transition temperature.[4] A cubic form can be synthezised at 1,000 K (730 °C; 1,340 °F),[2] and a hexagonal crystal structure can be formed at room temperature.[5]

The cubic form has each lanthanum atom surrounded by 32 hydrogen atoms, which form the vertices of an 18 faced shape called a chamfered cube.[6]

A similar compound lanthanum boron octahydride was computationally predicted to be a superconductor at 126 K with a pressure of 50 GPa.[7]

References

  1. "Lanthanum decahydride". https://www.acs.org/content/acs/en/molecule-of-the-week/archive/l/lanthanum-decahydride.html. 
  2. 2.0 2.1 2.2 Drozdov, A. P.; Kong, P. P.; Minkov, V. S.; Besedin, S. P.; Kuzovnikov, M. A.; Mozaffari, S.; Balicas, L.; Balakirev, F. F. et al. (2019). "Superconductivity at 250 K in lanthanum hydride under high pressures". Nature 569 (7757): 528–531. doi:10.1038/s41586-019-1201-8. PMID 31118520. 
  3. . doi:10.1038/s41598-020-58065-9. 
  4. Eremets, M. I.; Minkov, V. S.; Drozdov, A. P.; Kong, P. P.; Ksenofontov, V.; Shylin, S. I.; Bud'ko, S. L.; Prozorov, R. et al. (10 January 2022). "High‑Temperature Superconductivity in Hydrides: Experimental Evidence and Details". Journal of Superconductivity and Novel Magnetism. doi:10.1007/s10948-022-06148-1. 
  5. Geballe, Zachary M.; Liu, Hanyu; Mishra, Ajay K.; Ahart, Muhtar; Somayazulu, Maddury; Meng, Yue; Baldini, Maria; Hemley, Russell J. (15 January 2018). "Synthesis and Stability of Lanthanum Superhydrides". Angewandte Chemie International Edition 57 (3): 688–692. doi:10.1002/anie.201709970. PMID 29193506. 
  6. "NNNS chemistry blog: Lanthanum decahydride". http://chem.vander-lingen.nl/articles/Lanthanum_decahydride/id/894/itemid/895. 
  7. Di Cataldo, Simone; Heil, Christoph; von der Linden, Wolfgang; Boeri, Lilia (2021-07-29). "$\mathrm{La}{\mathrm{BH}}_{8}$: Towards high-${T}_{c}$ low-pressure superconductivity in ternary superhydrides". Physical Review B 104 (2): L020511. doi:10.1103/PhysRevB.104.L020511. https://link.aps.org/doi/10.1103/PhysRevB.104.L020511.