Indium(III) nitrate explained

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.^[1]

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:^[2]

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.^[3]

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.^{[4] [5]}

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.

Notes and References

1. Galina V. Kozhevnikova . Gábor Keresztury . The state of indium ions in nitrate solutions: A Raman spectroscopic study . Inorganica Chimica Acta . 1985 . 98 . 1 . 59–65 . 10.1016/S0020-1693(00)90751-5 . en.
2. D. G. Tuck . E. J. Woodhouse . P. Carty . Co-ordination compounds of indium. Part III. Indium(III) nitrate species . Journal of the Chemical Society A: Inorganic, Physical, Theoretical . 1966 . 1077–1080 . 10.1039/J19660001077 . en.
3. B. O. Field . C. J. Hardy . Volatile and anhydrous nitrato-complexes of metals: preparation by the use of dinitrogen pentroxide, and measurement of infrared spectra . Journal of the Chemical Society . 1964 . 4428–4434 . 10.1039/JR9640004428 . en.
4. Keita Yura . Karl C. Fredrikson . Egon Matijević . Preparation and properties of uniform colloidal indium compounds of different morphologies . Colloids and Surfaces . 1990 . 50 . 281–293 . 10.1016/0166-6622(90)80270-E . en.
5. Shcherbina, K. G.; Mokhosoev, M. V.; Gruba, A. I. . Reaction of aluminum and indium nitrates with sodium tungstate in hot solutions . ru . Zhurnal Neorganicheskoi Khimii . 1974 . 19 . 2 . 396–399 . 0044-457X .