Comparison of structural parameters for Zn/sub 4-x/Cd/sub x/Sb/sub 3/ compounds analyzed by the Rietveld method using two crystallographic models

A comparison of detailed structural parameters between the 3IS and Mayer models for the Zn/sub 4-x/Cd/sub x/Sb/sub 3/ system in the Zn-rich region has been successfully performed by the powder XRD study with the Rietveld method using 9 bulk crystals synthesized by vacuum casting method without annealing. The 3IS model gives a better fitting on the Rietveld analysis not only for the undoped Zn/sub 4/Sb/sub 3/ but also for the whole compositional range of the Zn-rich region of the Zn/sub 4-x/Cd/sub x/Sb/sub 3/ compounds. The purities and densities of the bulk crystals exceeded approximately 96 mass% and 95% of XRD density, respectively.