Samarium(III) oxalate

Samarium(III) oxalate is an inorganic chemical compound, a salt formed between the rare-earth element samarium in its +3 oxidation state and oxalate anions (C₂O₄²⁻). Its chemical formula is Sm₂(C₂O₄)₃.

It typically exists as a hydrate, meaning that water molecules are incorporated into the crystal structure. The degree of hydration can vary. For example, samarium(III) oxalate decahydrate (Sm₂(C₂O₄)₃·10H₂O) is a common form.

Samarium(III) oxalate is generally prepared by reacting a soluble samarium(III) salt (such as samarium(III) chloride or samarium(III) nitrate) with a soluble oxalate salt (such as sodium oxalate or ammonium oxalate) in an aqueous solution. A precipitate of samarium(III) oxalate forms.

Samarium(III) oxalate is practically insoluble in water. It decomposes upon heating to form samarium(III) oxide (Sm₂O₃). The thermal decomposition pathway often involves intermediate hydrates and anhydrous forms before the final oxide is obtained.

Samarium(III) oxalate has limited practical applications on its own, but it serves as an intermediate in the production of other samarium compounds, particularly samarium(III) oxide. It is also used in some research settings to study the properties of rare-earth oxalates and their thermal behavior.