High pressure crystal structure of PrN

Abstract

Compression of PrN yields a phase transformation to a tetragonal structure with ∼8.8 % volume collapse at ∼40 GPa at ambient temperature. A refinement reveals a distorted CsCl-like structure for the high pressure phase PrN(II), which is different from the high pressure phases seen among other lanthanide monopnictides. The space group of the new structure is P4/nmm (#129) with Pr in the 2c(0,1/2,0.3546) and N in the 2a(0,0,0) positions. PrN(II) persists to 85 GPa. © 2010 IOP Publishing Ltd.