Samarium(III) oxalate explained

Samarium(III) oxalate is an inorganic compound, a salt of samarium and oxalic acid with the formula Sm₂(C₂O₄)₃.^[1] The compound does not dissolve in water, forms a crystalline hydrate with yellow crystals.^[2]

Synthesis

Precipitation of soluble samarium salts with oxalic acid:^[3]

2SmCl _{3} +3H _{2C} _{2O} _{4} \xrightarrow{ Sm _{2 (C} _{2O} _{4)} _{3\downarrow} + 6 HCl }

Also a reaction of samarium nitrate and oxalic acid in an aqueous solution:

2Sm(NO _{3)} _{3} +3H _{2C} _{2O} _{4} \xrightarrow{ Sm _{2 (C} _{2O} _{4)} _{3\downarrow} + 6 HNO _{3} }

Physical properties

Samarium(III) oxalate forms a crystalline hydrate of the composition Sm₂(C₂O₄)₃ • 10H₂O with yellow crystals.

Chemical properties

Decomposes on heating:^[4]

Sm _{2(C} _{2O} _{4)} _{3} \xrightarrow{800 ^{oC} Sm _{2 O} _{3} + 3 CO _{2} + 3 CO }

Crystalline hydrate Sm₂(C₂O₄)₃ • 10H₂O decomposes stepwise.^[5]

Notes and References

1. Book: Bulletin of the Research Council of Israel: Chemistry. Section A . 1959 . Weizmann Science Press of Israel . 174 . 8 August 2021 . en.
2. Web site: Samarium(III) oxalate hydrate ≥99.99% Sigma-Aldrich . . 8 August 2021 . en.
3. Sanuki . Sumiko . Sugiyama . Akio . Tunekawa . Minoru . Kadomachi . Kiyotaka . Arai . Koichi . Precipitation Stripping of Samarium Oxalate from Organic Solution Containing Acid Type Extractant by Oxalic Acid . Journal of the Japan Institute of Metals . 1994 . 58 . 11 . 1271–1278 . 10.2320/jinstmet1952.58.11_1271 . 8 August 2021. free .
4. Wendlandt . W. W. . Thermal Decomposition of Rare Earth Metal Oxalates . . 1 March 1959 . 31 . 3 . 408–410 . 10.1021/ac60147a024 . 8 August 2021 . 0003-2700.
5. Formation and characterization of samarium oxide generated from different precursors . Thermochimica Acta . 3 June 2003 . 402 . 1–2 . 27–36 . 10.1016/S0040-6031(02)00535-X . 8 August 2021 . en . 0040-6031. Hussein . G.A.M. . Buttrey . D.J. . Desanto . P. . Abd-Elgaber . A.A. . Roshdy . Heba . Myhoub . Ali Y.Z. .