Energy States of Ni in Zn$\text{}_{1-x}$Mn$\text{}_{x}$Se:Ni Solid Solutions

Absorption and reflectivity measurements were carried out on Zn$\text{}_{1-x}$Mn$\text{}_{x}$Se:Ni solid solutions. The spectra demonstrate the radical change of the structure of internal Ni$\text{}^{2+}$(3d$\text{}^{8}$) transitions at the presence of the Mn ions and strong dependence on Mn concentration. The threshold energy ħω$\text{}_{th}$ for the process of Ni photoionization to the valence band Ni$\text{}^{2+}$(3d$\text{}^{8}$) + ħω$\text{}_{th}$ → Ni$\text{}^{1+}$(3d$\text{}^{9}$) + h is shifted to the lower energy by 30 meV, but hardly depends on x despite the essential increase in the energy gap.