Materials Data on NaYTi2(SiO5)2 by Materials Project
NaYTi2(SiO5)2 crystallizes in the monoclinic C2 space group. The structure is three-dimensional. Na1+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Na–O bond distances ranging from 2.31–2.73 Å. Y3+ is bonded to seven O2- atoms to form distorted YO7 pentagonal bipyramids that share corners with four SiO4 tetrahedra, edges with four equivalent TiO6 octahedra, and an edgeedge with one SiO4 tetrahedra. There are a spread of Y–O bond distances ranging from 2.21–2.53 Å. Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with two equivalent TiO6 octahedra, corners with four SiO4 tetrahedra, and edges with two equivalent YO7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 35–42°. There are a spread of Ti–O bond distances ranging from 1.85–2.08 Å. There are two inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with four equivalent TiO6 octahedra, corners with two equivalent YO7 pentagonal bipyramids, and an edgeedge with one YO7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 40–55°. There is two shorter (1.65 Å) and two longer (1.66 Å) Si–O bond length. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with four equivalent TiO6 octahedra and corners with two equivalent YO7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 38–52°. There is two shorter (1.64 Å) and two longer (1.66 Å) Si–O bond length. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to one Y3+ and two equivalent Ti4+ atoms. In the second O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+ and two equivalent Ti4+ atoms. In the third O2- site, O2- is bonded in a 4-coordinate geometry to one Na1+, one Y3+, one Ti4+, and one Si4+ atom. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to one Na1+, one Y3+, one Ti4+, and one Si4+ atom. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to one Y3+, one Ti4+, and one Si4+ atom. In the sixth O2- site, O2- is bonded in a distorted T-shaped geometry to one Na1+, one Ti4+, and one Si4+ atom.