Materials Data on Na2Ti2Si2O9 by Materials Project

Dataset · Wed Jul 15 04:00:00 EDT 2020

DOI:https://doi.org/10.17188/1277220· OSTI ID:1277220

Na2Ti2O2Si2O7 crystallizes in the orthorhombic Pbcn space group. The structure is three-dimensional. Na1+ is bonded to seven O2- atoms to form distorted NaO7 pentagonal bipyramids that share corners with three equivalent TiO6 octahedra, corners with two equivalent NaO7 pentagonal bipyramids, corners with two equivalent SiO4 tetrahedra, edges with three equivalent TiO6 octahedra, edges with two equivalent SiO4 tetrahedra, and a faceface with one NaO7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 49–65°. There are a spread of Na–O bond distances ranging from 2.36–2.61 Å. Ti4+ is bonded to six O2- atoms to form distorted TiO6 octahedra that share a cornercorner with one TiO6 octahedra, corners with three equivalent NaO7 pentagonal bipyramids, corners with three equivalent SiO4 tetrahedra, edges with two equivalent TiO6 octahedra, and edges with three equivalent NaO7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 40°. There are a spread of Ti–O bond distances ranging from 1.84–2.24 Å. Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with three equivalent TiO6 octahedra, corners with two equivalent NaO7 pentagonal bipyramids, corners with two equivalent SiO4 tetrahedra, and edges with two equivalent NaO7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 33–55°. 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 4-coordinate geometry to two equivalent Na1+ and two equivalent Si4+ atoms. In the second O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Ti4+, and one Si4+ atom. In the third O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Na1+, two equivalent Ti4+, and one Si4+ atom. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Na1+ and two equivalent Ti4+ atoms. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Na1+ and two equivalent Ti4+ atoms.

• Research Organization: LBNL Materials Project; Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
• Contributing Organization: The Materials Project; MIT; UC Berkeley; Duke; U Louvain
• DOE Contract Number: AC02-05CH11231
• OSTI ID: 1277220
• Report Number(s): mp-5996
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
Na-O-Si-Ti
Na2Ti2Si2O9
crystal structure