Structure and photoluminescence of ZnGa2Se4:Eu2+

The structure of undoped and europium-doped ZnGa2Se4 has been studied, and the interplanar spacings, the Miller indices of the observed reflections, and their relative intensities have been determined. The photoluminescence spectra of ZnGa2Se4 and ZnGa2Se4:Eu2+ crystals have been measured at temperatures from 77 to 230 K. The 566-nm band in the spectrum of ZnGa2Se4:Eu2+ is assigned to the Eu(2+)4f (6)5d -> 4f (7)((8) S (7/2)) electronic transition, and the bands at 591 and 646 nm are attributed to transitions of donor-acceptor pairs.