DOE OSTI2020
Li2SnP2O7 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are eight inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded in a 3-coordinate geometry to five O2- atoms. There are a spread of Li–O bond distances ranging from 1.96–2.54 Å. In the second Li1+ site, Li1+ is bonded in a rectangular see-saw-like geometry to four O2- atoms. There are a spread of Li–O bond distances ranging from 2.00–2.05 Å. In the third Li1+ site, Li1+ is bonded to four O2- atoms to form LiO4 tetrahedra that share corners with four PO4 tetrahedra, a cornercorner with one SnO5 trigonal bipyramid, corners with two LiO5 trigonal bipyramids, and an edgeedge with one LiO4 tetrahedra. There are a spread of Li–O bond distances ranging from 1.94–2.17 Å. In the fourth Li1+ site, Li1+ is bonded to five O2- atoms to form distorted LiO5 trigonal bipyramids that share corners with two LiO4 tetrahedra, corners with five PO4 tetrahedra, a cornercorner with one SnO5 trigonal bipyramid, an edgeedge with one SnO6 octahedra, and an edgeedge with one SnO5 trigonal bipyramid. There are a spread of Li–O bond distances ranging from 1.93–2.52 Å. In the fifth Li1+ site, Li1+ is bonded to five O2- atoms to form distorted LiO5 trigonal bipyramids that share corners with two LiO4 tetrahedra, corners with five PO4 tetrahedra, a cornercorner with one SnO5 trigonal bipyramid, an edgeedge with one SnO6 octahedra, and an edgeedge with one SnO5 trigonal bipyramid. There are a spread of Li–O bond distances ranging from 1.93–2.56 Å. In the sixth Li1+ site, Li1+ is bonded to four O2- atoms to form LiO4 tetrahedra that share corners with four PO4 tetrahedra, a cornercorner with one SnO5 trigonal bipyramid, corners with two LiO5 trigonal bipyramids, and an edgeedge with one LiO4 tetrahedra. There are a spread of Li–O bond distances ranging from 1.94–2.18 Å. In the seventh Li1+ site, Li1+ is bonded in a rectangular see-saw-like geometry to four O2- atoms. There are a spread of Li–O bond distances ranging from 2.00–2.04 Å. In the eighth Li1+ site, Li1+ is bonded in a 3-coordinate geometry to five O2- atoms. There are a spread of Li–O bond distances ranging from 1.96–2.56 Å. There are four inequivalent Sn2+ sites. In the first Sn2+ site, Sn2+ is bonded to six O2- atoms to form distorted SnO6 octahedra that share corners with six PO4 tetrahedra, an edgeedge with one LiO5 trigonal bipyramid, and an edgeedge with one SnO5 trigonal bipyramid. There are a spread of Sn–O bond distances ranging from 2.36–2.63 Å. In the second Sn2+ site, Sn2+ is bonded to five O2- atoms to form distorted SnO5 trigonal bipyramids that share a cornercorner with one LiO4 tetrahedra, corners with five PO4 tetrahedra, a cornercorner with one LiO5 trigonal bipyramid, an edgeedge with one SnO6 octahedra, and an edgeedge with one LiO5 trigonal bipyramid. There are a spread of Sn–O bond distances ranging from 2.30–2.69 Å. In the third Sn2+ site, Sn2+ is bonded to five O2- atoms to form distorted SnO5 trigonal bipyramids that share a cornercorner with one LiO4 tetrahedra, corners with five PO4 tetrahedra, a cornercorner with one LiO5 trigonal bipyramid, an edgeedge with one SnO6 octahedra, and an edgeedge with one LiO5 trigonal bipyramid. There are a spread of Sn–O bond distances ranging from 2.30–2.70 Å. In the fourth Sn2+ site, Sn2+ is bonded to six O2- atoms to form distorted SnO6 octahedra that share corners with six PO4 tetrahedra, an edgeedge with one LiO5 trigonal bipyramid, and an edgeedge with one SnO5 trigonal bipyramid. There are a spread of Sn–O bond distances ranging from 2.37–2.63 Å. There are eight 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, a cornercorner with one PO4 tetrahedra, corners with two equivalent LiO5 trigonal bipyramids, and corners with two SnO5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 49°. There are a spread of P–O bond distances ranging from 1.53–1.63 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one SnO6 octahedra, a cornercorner with one PO4 tetrahedra, corners with two LiO4 tetrahedra, a cornercorner with one SnO5 trigonal bipyramid, and corners with three LiO5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 53°. There are a spread of P–O bond distances ranging from 1.52–1.64 Å. In the third P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one SnO6 octahedra, a cornercorner with one PO4 tetrahedra, corners with two equivalent LiO4 tetrahedra, and corners with two SnO5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 68°. There are a spread of P–O bond distances ranging from 1.52–1.64 Å. In the fourth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three SnO6 octahedra and a cornercorner with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 42–68°. There are a spread of P–O bond distances ranging from 1.52–1.66 Å. In the fifth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three SnO6 octahedra and a cornercorner with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 42–68°. There are a spread of P–O bond distances ranging from 1.52–1.65 Å. In the sixth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one SnO6 octahedra, a cornercorner with one PO4 tetrahedra, corners with two equivalent LiO4 tetrahedra, and corners with two SnO5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 68°. There are a spread of P–O bond distances ranging from 1.52–1.64 Å. In the seventh P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one SnO6 octahedra, a cornercorner with one PO4 tetrahedra, corners with two equivalent LiO5 trigonal bipyramids, and corners with two SnO5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 49°. There are a spread of P–O bond distances ranging from 1.53–1.63 Å. In the eighth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one SnO6 octahedra, a cornercorner with one PO4 tetrahedra, corners with two LiO4 tetrahedra, a cornercorner with one SnO5 trigonal bipyramid, and corners with three LiO5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 53°. There are a spread of P–O bond distances ranging from 1.52–1.64 Å. There are twenty-eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to two Li1+ and one P5+ atom. In the second O2- site, O2- is bonded in a 2-coordinate geometry to one Li1+, one Sn2+, and one P5+ atom. In the third O2- site, O2- is bonded in a 1-coordinate geometry to two Sn2+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Li1+, one Sn2+, and one P5+ atom. In the fifth O2- site, O2- is bonded in a bent 120 degrees geometry to two P5+ atoms. In the sixth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Li1+, one Sn2+, and one P5+ atom. In the seventh O2- site, O2- is bonded in a distorted tetrahedral geometry to two Li1+, one Sn2+, and one P5+ atom. In the eighth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Li1+ and one P5+ atom. In the ninth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two P5+ atoms. In the tenth O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Li1+ and one P5+ atom. In the eleventh O2- site, O2- is bonded in a 1-coordinate geometry to one Li1+, two Sn2+, and one P5+ atom. In the twelfth O2- site, O2- is bonded in a 4-coordinate geometry to two Li1+, one Sn2+, and one P5+ atom. In the thirteenth O2- site, O2- is bonded in a 4-coordinate geometry to two Li1+, one Sn2+, and one P5+ atom. In the fourteenth O2- site, O2- is bonded in a 2-coordinate geometry to two Li1+, one Sn2+, and one P5+ atom. In the fifteenth O2- site, O2- is bonded in a 2-coordinate geometry to two Li1+, one Sn2+, and one P5+ atom. In the sixteenth O2- site, O2- is bonded in a 3-coordinate geometry to two Li1+, one Sn2+, and one P5+ atom. In the seventeenth O2- site, O2- is bonded in a 4-coordinate geometry to two Li1+, one Sn2+, and one P5+ atom. In the eighteenth O2- site, O2- is bonded in a 1-coordinate geometry to one Li1+, two Sn2+, and one P5+ atom. In the nineteenth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two P5+ atoms. In the twentieth O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Li1+ and one P5+ atom. In the twenty-first O2- site, O2- is bonded in a distorted trigonal planar geometry to two Li1+ and one P5+ atom. In the twenty-second O2- site, O2- is bonded in a distorted tetrahedral geometry to two Li1+, one Sn2+, and one P5+ atom. In the twenty-third O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Li1+, one Sn2+, and one P5+ atom. In the twenty-fourth O2- site, O2- is bonded in a bent 120 degrees geometry to two P5+ atoms. In the twenty-fifth O2- site, O2- is bonded in a 1-coordinate geometry to two Sn2+ and one P5+ atom. In the twenty-sixth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Li1+, one Sn2+, and one P5+ atom. In the twenty-seventh O2- site, O2- is bonded in a distorted trigonal planar geometry to two Li1+ and one P5+ atom. In the twenty-eighth O2- site, O2- is bonded in a 2-coordinate geometry to one Li1+, one Sn2+, and one P5+ atom.