The Stuffed Framework Structure of SrP 2 N 4 : Challenges to Synthesis and Crystal Structure Determination

SrP 2 N 4 was obtained by high‐pressure high‐temperature synthesis utilizing the multianvil technique (5 GPa, 1400 °C) starting from mixtures of phosphorus(V) nitride and strontium azide. SrP 2 N 4 turned out to be isotypic with BaGa 2 O 4 and is closely related to KGeAlO 4 . The crystal structure (SrP 2 N 4 , a =17.1029(8), c =8.10318(5) Å, space group P 6 3 (no. 173), V =2052.70(2) Å 3 , Z =24, R ( F 2 )=0.0633) was solved from synchrotron powder diffraction data by applying a combination of direct methods, Patterson syntheses, and difference Fourier maps adding the unit cell information derived from electron diffraction and symmetry information obtained from 31 P solid‐state NMR spectroscopy. The structure of SrP 2 N 4 was refined by the Rietveld method by utilizing both neutron and synchrotron X‐ray powder diffraction data, and has been corroborated additionally by 31 P solid‐state NMR spectroscopy by employing through‐bond connectivities and distance relations.