Gallium(III) sulfide

There are four polymorphs, α (hexagonal), α' (monoclinic), β(hexagonal) and γ(cubic). The alpha form is yellow. The crystal structures are related to those of ZnS with gallium in tetrahedral positions. The alpha and beta forms are isostructural with their aluminium analogues. The similarity in crystal form of gamma- with sphalerite (zinc blende), ZnS is believed to explain the enrichment of gallium in sphalerite ores. == Preparation and chemical properties ==

Ga2S3 can prepared by reacting the elements at high temperature or as a white solid by heating Ga in a stream of H2S at high temperature (950 °C). Ga2S3 decomposes at high temperature forming the non-stoichiometric sulfide, Ga4Sx (4.8 < x < 5.2). ==References==