Photoluminescence Properties of ZnF₂:Mn²⁺, (Zn, Mn)F₂ and MnF₂

抄録

Emission and excitation spectra and luminescence lifetimes of ZnF₂:Mn²⁺, (Zn, Mn)F₂ and MnF₂, all specimens in powder form, are observed at various temperatures between 2 and 300 K. The emission band of ZnF₂:Mn²⁺ is located at 583 nm at 300 K and 593 nm at temperatures below 80 K. The feature of the emission spectrum of (Zn_1−xMn_x)F₂ at 16 K is unchanged up to x=0.8. In MnF₂, the luminescence originates from Mn²⁺ ions perturbed by small concentrations of Zn²⁺, Ca²⁺ and other impurities. The intrinsic luminescence of pure MnF₂ is unobservable even at 2 K. The excitation spectra of ZnF₂:Mn²⁺, (Zn, Mn)F₂ and MnF₂ are extremely similar to each other because the electronic levels of the Mn²⁺ ion is determined predominantly in the cluster [MnF₆]⁴⁻ with a slightly distorted octahedral coordination.