Abstract
The bandgap energy of CdxZn1-xS at any given mole composition x in CdS is estimated by using, for the first time, the Redlich-Kister expression to examine the deviation to the linearity, for determining the corresponding thermodynamic interaction parameters, and interpret the sign of deviation to the linearity considered as ideal behavior. The current study introduces, for the first time, the concept of reduced Redlich-Kister function QY,T(xi) to bring to light the importance of interaction due to the progressive introduction of Cd into the pseudo-binary CdxZn1-xS and to reveal eventual specific characteristics of the studied pseudo-binary CdxZn1-xS. For the first time, as different from the bandgap energies EgCdS and EgZnS of the pure binary semiconductors ZnS and CdS, respectively, the concept of current bandgap energies Egc1(x) and Egc2(x) of each component CdS (1) and ZnS (2) within the system, respectively, is introduced. It indicates the effective individual contribution within the pseudo-binary CdxZn1-xS system at the given molar composition (x) of CdS. The study reveals that the concept of current bandgap energy is thermodynamically equivalent to the partial molar quantity, interesting to reveal the individual and effective contribution of Cd and Zn into the pseudo-binary CdxZn1-xS at a given mole composition (x).