The oxyhalides of indium

Abstract

The preparation of indium oxyiodide and indium oxyfluoride is reported for the first time, and an alternative preparation of the oxybromide and oxychloride is presented. An attempt to prepare pure indium oxycyanide was not successful, although some X-ray evidence for InOCN was obtained. Chemical properties of the compounds have been studied, and comparisons between the different oxyhalides are made. The oxyhalides react with acetylacetone to give indium trisacetylacetonate. With liquid N₂O₄ or with N₂O₄ and nitromethane mixtures, the oxyhalides react to give anhydrous indium trinitrate. For these reactions, as also for hydrolysis with water, the ease of reaction is InOl > InOBr > InOCl > InOF. The crystal structures of the new compounds have been studied by X-ray power methods. InOl crystallises with an orthorhombic unit cell containing two InOl units, with lattice spacings a= 4·05, b= 3·71, c= 9·49 Å. InOF crystallises with a hexagonal unit cell containing eighteen InOF units, with lattice spacings a= 10·83, c= 11·75 Å. The structures are compared with other stoicheiometrically similar oxyhalides.