Hochdruck‐Synthese,Kristallstruktur und Eigenschaften von NaPN2

High‐Pressure Synthesis, Crystal Structure, and Properties of NaPN₂ Single phase NaPN₂ was synthesized by the reaction of NaN₃ and P₃N₅ in a multianvil assembly at 3 GPa and 1000 °C. The title compound crystallizes in a variant of the chalcopyrite structure type and is isotypic to LiPN₂. The crystal structure was refined by the Rietveld method (I 4 2d, a = 497.21(2), c = 697.60(3) pm, Z = 4, 36 observed reflections, R_p = 0.0502, wR_p = 0.0649, R_F = 0.0788).     

Hochdrucksynthese von BaSr2P6N12 und BaCa2P6N12 und Strukturvergleich der Reihe BaP2N4, BaCa2P6N12 und BaSr2P6N12

High‐Pressure Synthesis of BaSr₂P₆N₁₂ and BaCa₂P₆N₁₂ and Comparison of the Structures of BaP₂N₄, BaCa₂P₆N₁₂, and BaSr₂P₆N₁₂ The novel nitridophosphates BaCa₂P₆N₁₂ and BaSr₂P₆ N₁₂ were obtained by means of high‐pressure high‐temperature synthesis utilizing the multianvil technique (1200 °C, 5 GPa). The complex anion [PN₂^?] of the title compound is formally isoelectronic with silica. The crystal structure was solved from powder data and refined by the Rietveld method (BaCa₂P₆N₁₂: , Z = 4, a = 9,9578(2) Å; BaSr₂P₆N₁₂: , Z = 4, 10,0705(2) Å). The crystal structures are derived from that of BaP₂N₄ which is isotypic with a high pressure phase of CaB₂O₄ and BaGa₂S₄. For each compound the ³¹P solid state NMR spectrum yielded a single resonance (BaCa₂P₆N₁₂: 7.4 ppm; BaSr₂P₆N₁₂:3.9 ppm).     

Structural Influence of Lone Pairs in GeP2N4, a Germanium(II) Nitridophosphate

Owing to their widespread properties, nitridophosphates are of high interest in current research. Explorative high-pressure high-temperature investigations yielded various compounds with stoichiometry MP₂N₄ (M=Be, Ca, Sr, Ba, Mn, Cd), which are discussed as ultra-hard or luminescent materials, when doped with Eu²⁺. Herein, we report the first germanium nitridophosphate, GeP₂N₄, synthesized from Ge₃N₄ and P₃N₅ at 6 GPa and 800 °C. The structure was determined by single-crystal X-ray diffraction and further characterized by energy-dispersive X-ray spectroscopy, density functional theory calculations, IR and NMR spectroscopy. The highly condensed network of PN₄-tetrahedra shows a strong structural divergence to other MP₂N₄ compounds, which is attributed to the stereochemical influence of the lone pair of Ge²⁺. Thus, the formal exchange of alkaline earth cations with Ge²⁺ may open access to various compounds with literature-known stoichiometry, however, new structures and properties.     

Zn8[P12N24]O2 – ein Nitridophosphat‐oxid mit Sodalith‐Struktur

Zn₈P₁₂N₂₄O₂ – a Nitridophosphate Oxide with Sodalite Structure The reaction between zinc metal and phosphorus nitride imide PN(NH) was investigated. Surprisingly, no Zn₆P₁₂N₂₄ was formed as assumed in former investigations but phase pure Zn₈[P₁₂N₂₄]O₂ ( (Nr. 217), a = 8.2422(2) Å; Z = 1) was obtained due to contamination by a small amount of oxygen. The existence of Zn₈[P₁₂N₂₄]O₂ was formerly supposed, but neither its crystal structure nor its exact composition have been unequivocally reported so far. The stoichiometric formula was deducted from elemental analyses, XANES spectroscopy at the phosphorus K‐threshold and IR‐spectroscopy using the crystallographic results of electron diffraction, X‐ray powder diffraction and solid‐state NMR spectroscopy. Zn₈[P₁₂N₂₄]O₂ adopts the sodalite structure type and is thus isotypic with Zn₈[P₁₂N₂₄]X₂ with X = S, Se, Te and Zn₈[B₁₂O₂₄]O₂.