Luminescence and scintillation properties of Ce3+-activated Cs2NaGdCl6, Cs3GdCl6, Cs2NaGdBr6 and Cs3GdBr6

Abstract We report on the structure, scintillation and luminescence properties of Cs 2 BGdX 6 :Ce (where B=Na, Cs; X=Cl, Br). Single crystals were obtained for four different compounds with both cubic and monoclinic structures. γ-ray spectroscopy measurements revealed light yields of 27,000 ph/MeV, 24,500 ph/MeV, 48,000 ph/MeV and 47,000 ph/MeV and energy resolutions of 4.0%, 4.5%, 3.3%, and 4.0% for Cs 2 NaGdCl 6 :Ce, Cs 3 GdCl 6 :Ce, Cs 2 NaGdBr 6 :Ce and Cs 3 GdBr 6 :Ce, respectively. X-ray emission and optical emission measurements of the samples exhibited both the characteristic Ce 3+ 5d–4f emission and the Gd 3+ 4f–4f emission. The optimal concentration of Ce 3+ for these compounds was also determined from X-ray excited luminescence decay measurements of polycrystalline forms of these materials.