An Unprecedented AB2 Tetrahedra Network Structure Type in a High-Pressure Phase of Phosphorus Oxonitride (PON)

摘要

Compounds exhibiting AB2-type tetrahedral network structures are versatile materials and of great technical importance. First of all microporous zeolites are known for their outstanding absorption properties and catalytic behavior and are therefore extensively used in industrial, agricultural, and laboratory environments. W However, the importance of dense AB2 networks should not be underestimated. SiO2 and to a minor extent GaPO4 are applied in piezoelectric devices, such as pressure sensors and microbalances, while quartz-like compounds in general, including phosphates such as AIPO4 and BPO4, can also be used for second-harmonic generation (SHG) purposes. Owing to the variety of applications, widespread research into novel AB2-type structures was conducted, including the prediction of more than two million unique prospective crystal structures for zeolites. However, only a minute subset of possible structures has been realized to date. In this search for new structure types, we have directed our attention to the system P-O-N, which is isoelectronic to silica.