From Framework to Layers Driven by Pressure – The Monophyllo‐Oxonitridophosphate β‐MgSrP3N5O2and Comparison to its α‐Polymorph

Abstract

AbstractOxonitridophosphates exhibit the potential for broad structural diversity, making them promising host‐compounds in phosphor‐converted light‐emitting diode applications. The novel monophyllo‐oxonitridophosphate β‐MgSrP3N5O2was obtained by using the high‐pressure multianvil technique. The crystal structure was solved and refined based on single‐crystal X‐ray diffraction data and confirmed by powder X‐ray diffraction. β‐MgSrP3N5O2crystallizes in the orthorhombic space groupCmme(no. 67,a=8.8109(6),b=12.8096(6),c=4.9065(3) Å,Z=4) and has a structure related to that of Ba2CuSi2O7. DFT calculations were performed to investigate the phase transition from α‐ to β‐MgSrP3N5O2and to confirm the latter as the corresponding high‐pressure polymorph. Furthermore, the luminescence properties of Eu2+doped samples of both polymorphs were investigated and discussed, showing blue and cyan emission, respectively (α‐MgSrP3N5O2;λmax=438 nm,fwhm=46 nm/2396 cm−1; β‐MgSrP3N5O2;λmax=502 nm,fwhm=42 nm/1670 cm−1).