Features of the Conduction-Band Electronic Structure of Manganese Sulfide Solid Solutions Doped with Lanthanides

Studying the X-ray absorption near-edge structure shows that cation substitution of a MnS matrix with lanthanide atoms does not significantly affect the character of the local environment of metal (manganese, dysprosium, thulium and ytterbium) and sulfur atoms in lanthanide-doped Ln 0.05 Mn 0.95 S ( Ln = Dy, Tm, Yb) solid solutions. Comparison of the experimental and theoretical data obtained by the finite-difference method has revealed that the main contributions of the unoccupied p- and d -states of manganese and p -states of sulfur are localized at the conduction-band bottom, both in the case of the initial MnS matrix and in the case of lanthanide-substituted Ln 0.05 Mn 0.95 S solid solutions. The main contributions of unoccupied f ‑states of ytterbium and thulium in Ln 0.05 Mn 0.95 S ( Ln = Tm, Yb) solid solutions are shifted to the high-energy region of the conduction band, while the f -states of dysprosium in dysprosium-doped Dy 0.05 Mn 0.95 S solid solutions are localized near the conduction-band bottom. According to the calculated model spectra, it is found that the contributions of the free lanthanide d -states in Ln 0.05 Mn 0.95 S ( Ln = Dy, Tm, Yb) solid solutions are shifted to the region of the conduction-band bottom with an increase of the atomic number of the lanthanide atom.