Indium di-iodide, InI₂

Indium di-iodide, InI₂, has not been isolated in the pure state, but thermal analysis shows that the compound exists. A mixture containing indium and iodine in the ratio In:I₂ melts at c. 212°, and the addition of either iodine or indium depresses the melting-point. The failure to obtain the di-iodide by heating the elements together in the correct ratio and distilling the product is doubtless due to dissociation of the molten di-iodide into the mono- and tri-iodides taking place to a very large extent, as the shape of the melting-point curve indicates.