Europium Lithosilicates LiEuSiN and LiEuSiO-Crystal Structures and Luminescence.

With LiEuSiN, the end member of the solid-solution series set up by substituting the divalent cation in the well-known host materials LiCaSiN and LiSrSiN with Eu(II) could be synthesized and described by means of single-crystal X-ray diffraction and single-grain luminescence spectroscopy. The new compound crystallizes isotypically to LiCaSiN and LiSrSiN in cubic space group 3̅ (no. 205) with a lattice parameter of = 10.7049(2) Å and a cell volume of = 1226.73(7) Å. Irradiated with blue light, LiEuSiN exhibits a narrow-band red emission (λ = 628 nm, 1.97 eV, 15924 cm; fwhm = 83 nm, 0.27 eV, 2143 cm). Also for LiEuSiO, the end member of the solid-solution series of LiSrSiO with Sr(II) substituted by Eu(II), luminescence emission could be measured on a single crystal (λ = 595 nm, 2.05 eV, 16798 cm; fwhm = 116 nm, 0.40 eV, 3211 cm). In this paper, both compounds are being compared with other known members of their solid-solution series regarding structure and luminescence properties.