Samarium(II) fluoride explained

Samarium(II) fluoride is one of fluorides of samarium with a chemical formula SmF₂. The compound crystalizes in the fluorite structure, and is significantly nonstoichiometric. Along with europium(II) fluoride and ytterbium(II) fluoride, it is one of three known rare earth difluorides, the rest are unstable.^[1]

Preparation

Samarium(II) fluoride can be prepared by using samarium or hydrogen gas to reduce samarium(III) fluoride:^[2]

2 SmF _{3} +Sm\longrightarrow3 SmF _{2} 2 SmF _{3} +H _{2} \longrightarrow2 SmF _{2} +2 HF

Properties

Samarium(II) fluoride is a purple to black solid. This is present in the crystal structure of the cubic calcium fluoride type (space group Fmm; No. 225 with a = 587.7 pm).^{[3] [4]}

Notes and References

1. Book: Greis . Ortwin . Haschke . John M. . Handbook on the Physics and Chemistry of Rare Earths Volume 5 . Chapter 45 Rare earth fluorides . Elsevier . 1982 . 5 . 0168-1273 . 10.1016/s0168-1273(82)05008-9 . 387–460. 9780444863751 .
2. Georg Brauer (Hrsg.), unter Mitarbeit von Marianne Baudler u. a.: Handbuch der Präparativen Anorganischen Chemie. 3., umgearbeitete Auflage. Band I, Ferdinand Enke, Stuttgart 1975,, S. 255.
3. Book: Ans . Jean d' . Taschenbuch für Chemiker und Physiker . Lax . Ellen . 1998 . Springer . 978-3-540-60035-0 . de.
4. Web site: mp-1206711: SmF2 (Cubic, Fm-3m, 225) . 2023-12-22 . Materials Project.