The crystal structure and luminescence properties of the first lithium oxonitridolithosilicate Li₃SiNO₂:Eu²

The compound Li₃SiNO₂:Eu²⁺ was synthesized in high temperature solid-state reactions in weld shut tantalum ampules and the crystal structure of Li₃SiNO₂ has been determined by single-crystal X-ray diffraction. It crystallizes in the monoclinic space group C2/c (no. 15) with the lattice parameters a = 1049.01(3), b = 1103.42(3), c = 511.86(2) pm, β = 116.14(1)°, and a volume of V = 0.53187(2) nm³. This compound is built up from two different layers, which are arranged alternately along the crystallographic a-axis. The results from single-crystal diffraction were confirmed by the Rietveld analysis of bulk samples. Moreover, Li₃SiNO₂ could be successfully doped with the activator ion Eu²⁺ and the luminescence spectroscopy of single-crystals revealed broad band emission at λ_max = 601 nm (fwhm = 90 nm).