Abstract

ZnS:Ni crystals exhibit at low temperatures a new emission [1] which is assigned to the transition ³T₁ (P) → ³T₁ (F) of the ${\text{Ni}}_{\text{Zn}}^{2+}(3{\text{d}}^8)$ ion, based on absorption data [2,3] and on preparation evidence. The structured emission spectrum observed in Ni-doped cubic crystals is superimposed on the tail of a broad Ni-related recombination band peaking at higher energy. A dip (c₁) coincides with the most prominent absorption line at $\overline{v}=12438$ cm⁻¹ thus indicating self-absorption. The luminescence is dominated by a sharp peak C₄ at $\overline{v}=12259$ cm⁻¹. By shifting the emission spectrum along the $\overline{v}$ abscissa such that C₄ coincides with the main emission line A₄ at $\overline{v}=4200$ cm⁻¹ representing the ³T₁(F) → ³T₁ (F) Ni²⁺ transition [3], a striking similarity of these structures is revealed (Fig.).

© 1984 Optical Society of America