SrH P N and SrP N : Insights into the Condensation Mechanism of Nitridophosphates under High Pressure.

The (imido)nitridophosphates SrH P N and SrP N were synthesized as colorless crystals by high-pressure/high-temperature reactions using the multianvil technique (5 GPa, ca. 1075 °C). Stoichiometric amounts of Sr(N ) P N , and amorphous HPN were used as starting materials. Whereas the crystal structure of SrH P N was solved and refined from single-crystal X-ray diffraction data and confirmed by Rietveld refinement, the structure of SrP N was determined from powder diffraction data. In order to confirm the structures, H and P solid-state NMR spectroscopy and FTIR spectroscopy were carried out. The chemical composition was confirmed with EDX measurements. Both compounds show unprecedented layered network structure types, built up from all-side vertex-sharing PN tetrahedra which are structurally related. The structural comparison of both compounds gives first insights into the hitherto unknown condensation mechanism of nitridophosphates under high pressure.