Indium(III) hydroxide is the

chemical compound A chemical compound is a chemical substance composed of many identical molecules (or molecular entities) containing atoms from more than one chemical element held together by chemical bonds. A molecule consisting of atoms of only one element ...

with the formula . Its prime use is as a precursor to indium(III) oxide, . It is sometimes found as the rare mineral dzhalindite. __TOC__

Structure

Indium(III) hydroxide has a cubic structure, space group Im3, a distorted structure.

Preparation and reactions

Neutralizing a solution containing an salt such as indium nitrate () or a solution of

indium trichloride Indium(III) chloride is the chemical compound with the formula which forms a tetrahydrate. This salt is a white, flaky solid with applications in organic synthesis as a Lewis acid. It is also the most available soluble derivative of indium. This ...

() gives a white precipitate that on aging forms indium(III) hydroxide. A

thermal decomposition Thermal decomposition, or thermolysis, is a chemical decomposition of a substance caused by heat. The decomposition temperature of a substance is the temperature at which the substance chemically decomposes. The reaction is usually endothermic ...

of freshly prepared shows the first step is the conversion of to cubic indium(III) hydroxide. The precipitation of indium hydroxide was a step in the separation of indium from

zincblende Sphalerite is a sulfide mineral with the chemical formula . It is the most important ore of zinc. Sphalerite is found in a variety of deposit types, but it is primarily in sedimentary exhalative, Mississippi-Valley type, and volcanogenic mas ...

ore by

Reich ( ; ) is a German word whose meaning is analogous to the English word " realm". The terms and are respectively used in German in reference to empires and kingdoms. In English usage, the term " Reich" often refers to Nazi Germany, also ca ...

and Richter, the discoverers of indium. Indium(III) hydroxide is

amphoteric In chemistry, an amphoteric compound () is a molecule or ion that can react both as an acid and as a base. What exactly this can mean depends on which definitions of acids and bases are being used. Etymology and terminology Amphoteric is d ...

, like gallium(III) hydroxide () and

aluminium hydroxide Aluminium hydroxide, , is found as the mineral gibbsite (also known as hydrargillite) and its three much rarer polymorphs: bayerite, doyleite, and nordstrandite. Aluminium hydroxide is amphoteric, i.e., it has both basic and acidic propert ...

(), but is much less acidic than gallium hydroxide (), having a lower solubility in alkaline solutions than in acid solutions. It is for all intents and purposes a basic hydroxide. Dissolving indium(III) hydroxide in strong alkali gives solutions that probably contain either four coordinate or . Reaction with acetic acid or carboxylic acids is likely to give the basic acetate or carboxylate salt, e.g. . At 10 MPa pressure and 250-400 °C, indium(III) hydroxide converts to indium oxide hydroxide (InO(OH)), which has a distorted rutile structure. Rapid decompression of samples of indium(III) hydroxide compressed at 34 GPa causes decomposition, yielding some indium metal. Laser ablation of indium(III) hydroxide gives indium(I) hydroxide (InOH), a bent molecule with an In-O-H angle of around 132° and an In-O bond length of 201.7 pm.

References

{{Hydroxides Indium compounds Hydroxides Inorganic compounds