Materials Data on Na6TiMn(SiO3)6 by Materials Project
Na6TiMn(SiO3)6 crystallizes in the trigonal R3m space group. The structure is three-dimensional. there are two inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to eight O2- atoms to form distorted NaO8 hexagonal bipyramids that share corners with four equivalent NaO8 hexagonal bipyramids, corners with two SiO4 tetrahedra, edges with two equivalent TiO6 octahedra, and edges with four SiO4 tetrahedra. There are a spread of Na–O bond distances ranging from 2.23–2.90 Å. In the second Na1+ site, Na1+ is bonded in a 2-coordinate geometry to eight O2- atoms. There are a spread of Na–O bond distances ranging from 2.29–2.96 Å. Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with six SiO4 tetrahedra and edges with six equivalent NaO8 hexagonal bipyramids. There is three shorter (1.91 Å) and three longer (2.07 Å) Ti–O bond length. Mn2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are three shorter (2.16 Å) and three longer (2.51 Å) Mn–O bond lengths. There are two inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one NaO8 hexagonal bipyramid, a cornercorner with one TiO6 octahedra, corners with two equivalent SiO4 tetrahedra, and edges with two equivalent NaO8 hexagonal bipyramids. The corner-sharing octahedral tilt angles are 31°. There are a spread of Si–O bond distances ranging from 1.57–1.67 Å. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one NaO8 hexagonal bipyramid, a cornercorner with one TiO6 octahedra, corners with two equivalent SiO4 tetrahedra, and edges with two equivalent NaO8 hexagonal bipyramids. The corner-sharing octahedral tilt angles are 40°. There are a spread of Si–O bond distances ranging from 1.62–1.67 Å. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Na1+, one Ti4+, one Mn2+, and one Si4+ atom. In the second O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two equivalent Na1+, one Ti4+, and one Si4+ atom. In the third O2- site, O2- is bonded in a 4-coordinate geometry to three Na1+ and one Si4+ atom. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to three Na1+ and two Si4+ atoms. In the fifth O2- site, O2- is bonded in a 5-coordinate geometry to three Na1+, one Mn2+, and one Si4+ atom.