Li_xH_12-x-y+z[P₁₂O_yN _24-y]X_z (X = Cl, Br) - Oxonitridophosphate mit NPO-zeolithstruktur

The oxonitridophosphates Li_xH_12-x-y+z[P ₁₂O_yN_24-y]Cl_z (1a) and Li _xH_12-x-y+z[P₁₂O_yN _24-y]Br_z (1b) were obtained by the reaction of Li ₂S, SP(NH₂)₃, OP(NH₂)₃ and NH₄Cl or NH₄Br, respectively, in closed ampoules at 700°C in a tube furnace. The crystal structure of Li_xH _12-x-y+z[P₁₂O_yN_24-y]X_z (X = Cl, Br) (1) was elucidated by means of X-ray diffraction of single crystals of 1a and of mixed single crystals 1ab (Pna2₁; a = 475.3(1) pm, b = 1420.8(3) pm, c = 820.3(2) pm (1a) and a = 476.6(1) pm, b = 1426.3(3) pm, c = 823.5(2) pm (1ab), respectively; Z = 1) and via X-ray diffraction, neutron diffraction, electron diffraction and solid state NMR spectroscopy of powder samples of 1a. The anionic network is composed of corner-sharing P(O,N) ₄-tetrahedra forming 12-ring channels. The lithium and the halide ions are located in these channels. The chemical composition of the samples was determined by EDX analysis and chemical elemental analysis. IR and Raman spectroscopic properties as well as the thermal behaviour were investigated. Impedance spectroscopic measurements showed a lithium ion conductivity.