Preparation and phase relationships in systems of the type CdSM IM IIIS 2 where M I = Ag, Cu and M III = Al, Ga, In

Systems of the type M ^IM ^IIIS ₂ (chalcopyrite)-CdS (wurtzite) where M ^I = Ag, Cu and M ^III = Al, Ga, In were investigated to determine the regions of mutual solid solubility. It was found that the chalcopyrite structure could not tolerate extensive CdS substitution. When M ^III was Al or Ga the solubility of M ^IM ^IIIS ₂ in CdS was also very limited. However, when M ^III = In ( r_{In ³⁺} ≫ r_{Ga ³⁺} > r_{Al ³⁺}), the solubility of M ^IInS ₂ in CdS was quite extensive (∼50%). These results are consistent with a prior study on systems of the type M ^IM ^IIIS ₂ZnS which indicated that in sulfides, larger cations tend to result in the formation of new quaternary, wurtzite phases.