Crystalline Nitridophosphates by Ammonothermal Synthesis

Nitridophosphates are a well‐studied class of compounds with high structural diversity. However, their synthesis is quite challenging, particularly due to the limited thermal stability of starting materials like P(3)N(5). Typically, it requires even high‐pressure techniques (e.g. multianvil) in most cases. Herein, we establish the ammonothermal method as a versatile synthetic tool to access nitridophosphates with different degrees of condensation. α‐Li(10)P(4)N(10), β‐Li(10)P(4)N(10), Li(18)P(6)N(16), Ca(2)PN(3), SrP(8)N(14), and LiPN(2) were synthesized in supercritical NH(3) at temperatures and pressures up to 1070 K and 200 MPa employing ammonobasic conditions. The products were analyzed by powder X‐ray diffraction, energy dispersive X‐ray spectroscopy, and FTIR spectroscopy. Moreover, we established red phosphorus as a starting material for nitridophosphate synthesis instead of commonly used and not readily available precursors, such as P(3)N(5). This opens a promising preparative access to the emerging compound class of nitridophosphates.