Materials Data on NaSn2(PO4)3 by Materials Project
NaSn2(PO4)3 crystallizes in the trigonal R-3 space group. The structure is three-dimensional. there are two inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded in a distorted hexagonal planar geometry to six equivalent O2- atoms. All Na–O bond lengths are 2.56 Å. In the second Na1+ site, Na1+ is bonded in a distorted hexagonal planar geometry to six equivalent O2- atoms. All Na–O bond lengths are 2.51 Å. There are two inequivalent Sn4+ sites. In the first Sn4+ site, Sn4+ is bonded to six O2- atoms to form SnO6 octahedra that share corners with six equivalent PO4 tetrahedra. There are three shorter (2.04 Å) and three longer (2.07 Å) Sn–O bond lengths. In the second Sn4+ site, Sn4+ is bonded to six O2- atoms to form SnO6 octahedra that share corners with six equivalent PO4 tetrahedra. There are three shorter (2.03 Å) and three longer (2.07 Å) Sn–O bond lengths. P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with four SnO6 octahedra. The corner-sharing octahedra tilt angles range from 27–41°. There is two shorter (1.54 Å) and two longer (1.55 Å) P–O bond length. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Sn4+, and one P5+ atom. In the second O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Sn4+, and one P5+ atom. In the third O2- site, O2- is bonded in a bent 150 degrees geometry to one Sn4+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a bent 150 degrees geometry to one Sn4+ and one P5+ atom.