Studies on absorption spectra of mixed zinc cadmium sulphide microparticles stabilized in AOT-heptane-water and CTAB-chloroform-water inverse micellar systems

Ultrafine particles composed of mixed crystals of ZnxCd1-xS can be generated in situ in AOT-heptane-water and CTAB-chloroform-water microemulsions using an ultrasonic processor. The microcrystallites exhibit the ''quantum size effect''. The composition of mixed sulphides and the water content (pool size) of inverted micelles can be varied systematically and the band gap energies of the semiconductor particles can be determined from the photoabsorption thresholds (edges). The experimental results reveal that a homogeneous solid solution of two sulphides is formed in CTAB-chloroform-water system. A method is proposed for determining the bulk optical dielectric constants of solid solutions of two semiconductors employing the Brus equation.