Indium(III) nitrate is a nitrate salt of indium which forms various hydrates. Only the pentahydrate has been crystallographically verified. Other hydrates are also reported in literature, such as the trihydrate.
Production and reactions
Indium(III) nitrate hydrate is produced by the dissolution of indium metal in concentrated nitric acid followed by evaporation of the solution: In + 4 HNO3 → In(NO3)3 + NO + 2 H2O The hydrate first decomposes to a basic salt and then to indium(III) oxide at 240 °C. Anhydrous indium(III) nitrate is claimed to be produced by the reaction of anhydrous indium(III) chloride and dinitrogen pentoxide.
In the presence of excess nitrate ions, indium(III) nitrate converts to the [In(NO3)4]- ion.
The hydrolysis of indium(III) nitrate yields indium(III) hydroxide. It also reacts with sodium tungstate to form In(OH)WO4, [In(OH)2]2WO4, NaInWO4 or In2(WO4)3 depending on pH.
Structure
Only the pentahydrate has been structurally elucidated. The pentahydrate consists of octahedral [In(NO3)(H2O)5]2+ centers as well as two nitrates and is monoclinic.