Substitutional disorder in Sr_2−yEu_yB_2−2xSi_2+3xAl_2−xN_8+x (x ≃ 0.12, y ≃ 0.10)

A novel nitride was synthesized from Sr₃N₂, EuN, Si₃N₄, AlN and BN under nitro­gen gas pressure. The structure consists of a host framework with Sr/Eu atoms accommodated in the cavities. The host framework is constructed by the linkage of MN₄ tetra­hedra (M = Si, Al) and BN₃ triangles, and contains substitutional disorder described by the alternative occupation of B₂ or Si₂N on the (0, 0, z) axis.