Sr<sub>3</sub>P<sub>3</sub>N<sub>7</sub>: Complementary Approach by Ammonothermal and High‐Pressure Syntheses
Mathias Mallmann, Sebastian Wendl, Philipp Strobel, Peter J. Schmidt, Wolfgang Schnick
Abstract
Abstract Nitridophosphates exhibit an intriguing structural diversity with different structural motifs, for example, chains, layers or frameworks. In this contribution the novel nitridophosphate Sr 3 P 3 N 7 with unprecedented dreier double chains is presented. Crystalline powders were synthesized using the ammonothermal method, while single crystals were obtained by a high‐pressure multianvil technique. The crystal structure of Sr 3 P 3 N 7 was solved and refined from single‐crystal X‐ray diffraction and confirmed by powder X‐ray methods. Sr 3 P 3 N 7 crystallizes in monoclinic space group P 2/ c . Energy‐dispersive X‐ray and Fourier‐transformed infrared spectroscopy were conducted to confirm the chemical composition, as well as the absence of NH x functionality. The optical band gap was estimated to be 4.4 eV using diffuse reflectance UV/Vis spectroscopy. Upon doping with Eu 2+ , Sr 3 P 3 N 7 shows a broad deep‐red to infrared emission (λ em =681 nm, fwhm≈3402 cm −1 ) with an internal quantum efficiency of 42 %.