Materials Data on NaSiBO4 by Materials Project
NaBSiO4 crystallizes in the hexagonal P6_3 space group. The structure is three-dimensional. there are three inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Na–O bond distances ranging from 2.60–2.70 Å. In the second Na1+ site, Na1+ is bonded to six O2- atoms to form distorted NaO6 pentagonal pyramids that share corners with six equivalent SiO4 tetrahedra, edges with three equivalent BO4 tetrahedra, and a faceface with one NaO6 octahedra. There are three shorter (2.28 Å) and three longer (2.41 Å) Na–O bond lengths. In the third Na1+ site, Na1+ is bonded to six O2- atoms to form NaO6 octahedra that share corners with six equivalent BO4 tetrahedra, corners with six equivalent SiO4 tetrahedra, and a faceface with one NaO6 pentagonal pyramid. There are three shorter (2.41 Å) and three longer (2.60 Å) Na–O bond lengths. B3+ is bonded to four O2- atoms to form BO4 tetrahedra that share corners with two equivalent NaO6 octahedra, corners with four equivalent SiO4 tetrahedra, and an edgeedge with one NaO6 pentagonal pyramid. The corner-sharing octahedra tilt angles range from 62–71°. There are a spread of B–O bond distances ranging from 1.48–1.50 Å. Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two equivalent NaO6 octahedra, corners with two equivalent NaO6 pentagonal pyramids, and corners with four equivalent BO4 tetrahedra. The corner-sharing octahedra tilt angles range from 58–84°. There is one shorter (1.63 Å) and three longer (1.64 Å) Si–O bond length. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to one Na1+, one B3+, and one Si4+ atom. In the second O2- site, O2- is bonded in a 2-coordinate geometry to two Na1+, one B3+, and one Si4+ atom. In the third O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Na1+, one B3+, and one Si4+ atom. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to two Na1+, one B3+, and one Si4+ atom.