Materials Data on Na2ZrSi2O7 by Materials Project

Abstract

Na2ZrSi2O7 is Esseneite-like structured and crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are two inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Na–O bond distances ranging from 2.39–3.07 Å. In the second Na1+ site, Na1+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Na–O bond distances ranging from 2.48–2.93 Å. Zr4+ is bonded to six O2- atoms to form ZrO6 octahedra that share corners with six SiO4 tetrahedra. There are a spread of Zr–O bond distances ranging from 2.08–2.17 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 three equivalent ZrO6 octahedra and a cornercorner with one SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 28–54°. There are a spread of Si–O bond distances ranging from 1.62–1.69 Å. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with three equivalent ZrO6 octahedra and a cornercorner with one SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 8–50°. There are a spread of Si–O bond distances ranging from 1.62–1.69 Å. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Zr4+, and one Si4+ atom. In the second O2- site, O2- is bonded in a 5-coordinate geometry to three equivalent Na1+, one Zr4+, and one Si4+ atom. In the third O2- site, O2- is bonded in a 4-coordinate geometry to three equivalent Na1+ and two Si4+ atoms. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Na1+, one Zr4+, and one Si4+ atom. In the fifth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two Na1+, one Zr4+, and one Si4+ atom. In the sixth O2- site, O2- is bonded in a 1-coordinate geometry to three Na1+, one Zr4+, and one Si4+ atom. In the seventh O2- site, O2- is bonded in a 2-coordinate geometry to two Na1+, one Zr4+, and one Si4+ atom.