Materials Data on Na3SiSnBO7 by Materials Project
Na3BSnSiO7 crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional. there are two inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Na–O bond distances ranging from 2.36–2.88 Å. In the second Na1+ site, Na1+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Na–O bond distances ranging from 2.23–2.93 Å. B3+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of B–O bond distances ranging from 1.35–1.42 Å. Sn4+ is bonded to six O2- atoms to form SnO6 octahedra that share corners with four equivalent SiO4 tetrahedra. There are a spread of Sn–O bond distances ranging from 2.06–2.15 Å. Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with four equivalent SnO6 octahedra. The corner-sharing octahedra tilt angles range from 41–52°. There is three shorter (1.64 Å) and one longer (1.67 Å) Si–O bond length. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a 5-coordinate geometry to four Na1+ and one B3+ atom. In the second O2- site, O2- is bonded in a 1-coordinate geometry to three Na1+, one B3+, and one Sn4+ atom. In the third O2- site, O2- is bonded in a 1-coordinate geometry to three Na1+, one B3+, and one Sn4+ atom. In the fourth O2- site, O2- is bonded in a 1-coordinate geometry to three Na1+, one Sn4+, and one Si4+ atom. In the fifth O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Na1+, one Sn4+, and one Si4+ atom. In the sixth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two equivalent Na1+, one Sn4+, and one Si4+ atom.