Einsteinium(III) oxide

__ Es3+     __ O2−
IUPAC names
Einsteinium sesquioxide
Dieinsteinium trioxide
Einsteinium(III) oxide
Molar mass 554 g/mol (253Es)
Appearance colourless solid[1]
a = 370 pm, c = 600 pm[2]
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

Einsteinium(III) oxide is an oxide of the synthetic actinide einsteinium which has the molecular formula Es2O3. It is a colourless solid.[1]

Three modifications are known. The body-centered cubic form has lattice parameter a = 1076.6 ± 0.6 pm; this allows the ionic radius of the Es3+ ion to be calculated as 92.8 pm.[3] The other two forms are monoclinic and hexagonal: the hexagonal form has the lanthanum(III) oxide structure.[4]

Einsteinium(III) oxide can be obtained by annealing einsteinium(III) nitrate in sub-microgram quantities.[3]


  1. ^ a b Arnold F. Holleman, Nils Wiberg: Lehrbuch der Anorganischen Chemie, 102nd Edition, de Gruyter, Berlin 2007, ISBN 978-3-11-017770-1, p. 1972.
  2. ^ Christine Guéneau; Alain Chartier; Paul Fossati; Laurent Van Brutzel; Philippe Martin (2020). "Thermodynamic and Thermophysical Properties of the Actinide Oxides". Comprehensive Nuclear Materials 2nd Ed. 7: 111–154. doi:10.1016/B978-0-12-803581-8.11786-2. ISBN 9780081028667. S2CID 261051636.
  3. ^ a b R. G. Haire, R. D. Baybarz: "Identification and Analysis of Einsteinium Sesquioxide by Electron Diffraction", in: Journal of Inorganic and Nuclear Chemistry, 1973, 35 (2), S. 489–496; doi:10.1016/0022-1902(73)80561-5.
  4. ^ R. G. Haire, L. Eyring, in: Handbook on the Physics and Chemistry of Rare Earths, Vol. 18 Lanthanoids and Actinides Chemistry (hrsg. von K. A. Gscheidner, Jr., L. Eyring, G. R. Choppin, G. H. Lander), North-Holland, New York 1994, S. 414–505.

Further reading