Materials Data on TiSn(PO4)2 by Materials Project
TiSn(PO4)2 crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional. Ti4+ is bonded to six O2- atoms to form distorted TiO6 pentagonal pyramids that share corners with four equivalent SnO6 octahedra, corners with four PO4 tetrahedra, and an edgeedge with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 41–59°. There are a spread of Ti–O bond distances ranging from 1.91–2.07 Å. Sn2+ is bonded to six O2- atoms to form distorted SnO6 octahedra that share corners with four equivalent TiO6 pentagonal pyramids, corners with four PO4 tetrahedra, and an edgeedge with one PO4 tetrahedra. There are a spread of Sn–O bond distances ranging from 2.22–2.65 Å. There are two inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one SnO6 octahedra, corners with three equivalent TiO6 pentagonal pyramids, and an edgeedge with one SnO6 octahedra. The corner-sharing octahedral tilt angles are 53°. There are a spread of P–O bond distances ranging from 1.52–1.58 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three equivalent SnO6 octahedra, a cornercorner with one TiO6 pentagonal pyramid, and an edgeedge with one TiO6 pentagonal pyramid. The corner-sharing octahedra tilt angles range from 24–71°. There are a spread of P–O bond distances ranging from 1.49–1.59 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Ti4+ and one P5+ atom. In the second O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Sn2+ and one P5+ atom. In the third O2- site, O2- is bonded in a 3-coordinate geometry to one Ti4+, one Sn2+, and one P5+ atom. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to one Ti4+, one Sn2+, and one P5+ atom. In the fifth O2- site, O2- is bonded in a linear geometry to one Ti4+ and one P5+ atom. In the sixth O2- site, O2- is bonded in a distorted single-bond geometry to one Sn2+ and one P5+ atom.