Optical transitions of Ni2+and radiation defects in MgF2and MnF2

A study has been made of the absorption, emission and excitation spectra of transitions in nickel-doped MgF 2 and MnF 2 . The temperature dependence of the lifetimes of these transitions has been recorded. For the case MgF 2 :Ni 2+ , a complete configuration coordinate model has been determined for this crystal using the method of Struck and Fonger (1974). Similar observations have been made for MnF 2 :Ni 2+ , but energy transfer between Mn 2+ ions and Ni 2+ ions reduces the amount of information available for completion of the model. It is found that the infrared luminescence intensity of MnF 2 :Ni 2+ for excitation in the visible region (400-600 nm) is twice that of MgF 2 :Ni 2+ . No observable changes occurred in the Ni 2+ optical transitions when these crystals were irradiated with 1.7 MeV electrons.