Transition Metal Impurities and Electronic Structure of ZnSe-Based Isovalent Semiconductor Alloys

Energy level positions of the nickel 2+/1+ and cobalt 2+/3+ charge states have been used to estimate band edges for the valence and conduction bands of ZnSe-based alloys with cation (ZnCdSe) and anion (ZnSSe) substitution. Chemical trends in band offsets of heterostructures of Zn- or Mn-based II-VI compounds are analysed. Further on, the change of Ni$\text{}^{2+}$(3d$\text{}^{8}$) and Co$\text{}^{2+}$(3d$\text{}^{7}$) intra-d shell transition bands upon the alloying of host material is discussed.