Samarium(III) oxalate

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

Synthesis
Precipitation of soluble samarium salts with oxalic acid:


 * $$\mathsf{ 2SmCl_3 + 3H_2C_2O_4 \ \xrightarrow{}\ Sm_2(C_2O_4)_3\downarrow + 6HCl }$$

Also a reaction of samarium nitrate and oxalic acid in an aqueous solution:
 * $$\mathsf{ 2Sm(NO_3)_3 + 3H_2C_2O_4 \ \xrightarrow{}\ Sm_2(C_2O_4)_3\downarrow + 6HNO_3 }$$

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

Chemical properties
Decomposes on heating:


 * $$\mathsf{ Sm_2(C_2O_4)_3 \ \xrightarrow{800^oC}\ Sm_2O_3 + 3CO_2 + 3CO }$$

Crystalline hydrate Sm2(C2O4)3 • 10H2O decomposes stepwise.