STUDY ON THE CRYSTALLOGRAPHIC AND PHOTOLUMINESCENT PROPERTIES OF CD3INGAS6 .1. CRYSTALLOGRAPHIC STUDY

X-ray studies of CdxInGaS3+x (1.0 less-than-or-equal-to x less-than-or-equal-to 3.5) were carried out to clarify the crystallographic state of Cd3InGaS6 which was found to show very intense green photoluminescence at low temperatures. The X-ray diffraction pattern showed that Cd3InGaS6 is a mixture of CdS and CdInGaS4. Relative intensity of the diffraction line at 2theta = 26.5-degrees to two adjacent lines, where theta is the Bragg angle, indicates that CdS and CdInGaS4 are laminated in the direction of the c-axis of the hexagonal structure. A computer simulation of the diffraction pattern based on the laminated model was carried out and could nearly reproduce the experimental diffraction pattern. The X-ray diffraction from the growth face of the crystals and the Weissenberg photograph revealed the laminated structure.