Materials Data on NaHf2(PO4)3 by Materials Project

Abstract

NaHf2(PO4)3 crystallizes in the trigonal R-3c space group. The structure is three-dimensional. Na1+ is bonded in a distorted hexagonal planar geometry to six equivalent O2- atoms. All Na–O bond lengths are 2.57 Å. Hf4+ is bonded to six O2- atoms to form HfO6 octahedra that share corners with six equivalent PO4 tetrahedra. There are three shorter (2.04 Å) and three longer (2.09 Å) Hf–O bond lengths. P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with four equivalent HfO6 octahedra. The corner-sharing octahedra tilt angles range from 23–36°. There is two shorter (1.54 Å) and two longer (1.55 Å) P–O bond length. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to one Na1+, one Hf4+, and one P5+ atom. In the second O2- site, O2- is bonded in a bent 150 degrees geometry to one Hf4+ and one P5+ atom.