CdP2N4 and MnP2N4 – Ternary Transition‐Metal Nitridophosphates. Issue 10 (4th March 2016)

• Record Type: Journal Article
• Authors: Pucher, Florian J.; Karau, Friedrich W.; Schmedt auf der Günne, Jörn; Schnick, Wolfgang
• Is Part Of: European journal of inorganic chemistry. Issue 10(2016)
• Page Start: 1497
• Page End: 1502
• Publication Date: 2016-03-04
• Subjects: High‐pressure synthesis -- Electron diffraction -- Phosphorus -- Nitrides; Chemistry, Inorganic -- Periodicals; Organometallic chemistry -- Periodicals; Bioinorganic chemistry -- Periodicals; Solid state chemistry -- Periodicals; 546
• DOI: 10.1002/ejic.201600042
• Languages: English
• ISSNs: 1434-1948

Abstract

Abstract: The ternary transition‐metal nitridophosphates CdP2 N4 and MnP2 N4 have been synthesized under high‐pressure high‐temperature conditions (5–8 GPa, 1000–1300 °C) by using the multianvil technique. Cd and Mn azides can be used as the starting materials, however, with respect to safety considerations, it is much more advantageous to start from metal powders and phosphorus nitride imide, HPN2 . Both nitridophosphates crystallize in a structure closely related to the megacalsilite structure type. As a result of the known issues concerning superstructures with this type of structure, TEM investigations were performed on CdP2 N4, which revealed that the megacalsilite superstructure is not equally pronounced in all crystallites. By adding NH4 Cl as mineralizer, single crystals were obtained that exhibit unequally pronounced superstructure reflections. Consequently, an averaged structural model was used and refined by the Rietveld method [ P 63 22, a = 16.7197(3), c = 7.6428(2) Å, V = 1850.3(2) Å 3, R p = 0.0671, wR p = 0.0869 for CdP2 N4 and P 63 22, a = 16.5543(2), c = 7.5058(2) Å, V = 1781.3(1) Å 3, R p = 0.0526, wR p = 0.0697 for MnP2 N4 ]. The 31 P NMR spectra exhibit four signal groups at (6.4, 4.8), 0.8, and –9.7 ppm with pronounced shoulders belonging to the same phase in an approximate area ratio of 4.8:1.1:2.0, thereby proving at least eight P sites. Abstract : CdP2 N4 and MnP2 N4 represent ternary transition‐metal nitridophosphates. A combination of powder and single‐crystal X‐ray diffraction, NMR spectroscopy, and electron diffraction was used to elucidate and verify their structures. The compounds exhibit three different types of superstructures similar to megacalsilite‐type SrP2 N4 .