Materials Data on NaCuPO4 by Materials Project
NaCuPO4 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. Na1+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Na–O bond distances ranging from 2.36–2.80 Å. There are two inequivalent Cu2+ sites. In the first Cu2+ site, Cu2+ is bonded to six O2- atoms to form CuO6 octahedra that share corners with six equivalent PO4 tetrahedra. There are a spread of Cu–O bond distances ranging from 1.98–2.49 Å. In the second Cu2+ site, Cu2+ is bonded in a square co-planar geometry to four O2- atoms. There is two shorter (1.94 Å) and two longer (2.03 Å) Cu–O bond length. P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three equivalent CuO6 octahedra. The corner-sharing octahedra tilt angles range from 41–53°. There are a spread of P–O bond distances ranging from 1.54–1.57 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Na1+, one Cu2+, and one P5+ atom. In the second O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Na1+, one Cu2+, and one P5+ atom. In the third O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Na1+, one Cu2+, and one P5+ atom. In the fourth O2- site, O2- is bonded in a 5-coordinate geometry to two equivalent Na1+, two Cu2+, and one P5+ atom.