Crystal growth and optical properties of CdGa2S4

High optical quality crystals of CdGa2S4 have been grown from the melt by the vertical Bridgman method. Melt composition was found to affect both the color of the crystals (varying shades of pale yellow) and the occurence of optical scattering defects. The scattering defects are thought to be precipitates caused by retrograde solubility; however, their composition is currently unknown. Quantitative electron microprobe analysis and differential thermal analysis were used to confirm the identity of the CdGa2S4 phase, and its congruent melting behavior at 980°±5°C. Our results verify the phase equilibria proposed by Radaoustan and co-workers.