Indium(I) iodide

Indium monoiodide is a binary inorganic compound of indium metal and iodine with the chemical formula InI.

Preparation
Indium(I) iodide can be obtained by reacting indium with iodine or indium(III) iodide in vacuum at 300 °C to 400 °C or with mercury(II) iodide at 350 °C.
 * 2In + I2 -> 2InI
 * 2In + InI3 -> 3InI
 * 2In + HgI2 -> 2InI + Hg

Physical properties
Indium(I) iodide forms a brown-red diamagnetic solid. Its melt is black. The compound has an orthorhombic crystal structure in the space group Cmcm (space group no. 63) with the lattice parameters a = 475 pm, b = 1276 pm, c = 491 pm.

Chemical properties
Decomposes slowly with hot water:
 * 2InI + H2O -> InOH + HI

Reacts with water in the presence of oxygen:
 * 2InI + O + 3H2O -> 2In(OH)2 + 2HI