• cadmium zinc sulfide;
  • density functional theory;
  • solid solutions

Cd1−xZnxS solid solutions have drawn much attention for the extensive potential applications. In this paper, we systematically computed the lattice constant, mixing enthalpy and bandgap for each configuration of zinc-blende (ZB) and wurtzite (WZ) type Cd1−xZnxS (x = 0, 0.25, 0.5, 0.75, 1) solid solutions using the first-principles method, and quantitatively revealed that the Zn–S bond was the most critical factor in determining the relative stability among different configurations with the same composition, as well as the order of the bandgap. Using the configuration-averaged method, the average values of these properties, as well as the optical bowing coefficient, were obtained. We estimated the influence of the configuration average on these quantities, indicating that the configuration average significantly affected the mixing enthalpy, which explicitly determined the phase stability of the solid solutions.