Materials Data on Na2MgSi5O12 by Materials Project

Abstract

Na2MgSi5O12 is Esseneite-like structured and crystallizes in the orthorhombic Ibca space group. The structure is three-dimensional. there are two inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded in a distorted body-centered cubic geometry to eight O2- atoms. There are a spread of Na–O bond distances ranging from 2.27–2.46 Å. In the second Na1+ site, Na1+ is bonded in a distorted body-centered cubic geometry to eight O2- atoms. There are a spread of Na–O bond distances ranging from 2.28–2.46 Å. Mg2+ is bonded in a distorted body-centered cubic geometry to eight O2- atoms. There are a spread of Mg–O bond distances ranging from 2.17–2.43 Å. There are five inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to four O2- atoms to form corner-sharing SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 41–43°. There is two shorter (1.64 Å) and two longer (1.66 Å) Si–O bond length. In the second Si4+ site, Si4+ is bonded to six O2- atoms to form corner-sharing SiO6 octahedra. There are a spread of Si–O bond distances ranging from 1.80–1.83 Å. In the third Si4+ site, Si4+ is bonded to six O2- atoms to form corner-sharing SiO6 octahedra. There is four shorter (1.80 Å) and two longer (1.83 Å) Si–O bond length. In the fourth Si4+ site, Si4+ is bonded to four O2- atoms to form corner-sharing SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 45°. All Si–O bond lengths are 1.66 Å. In the fifth Si4+ site, Si4+ is bonded to four O2- atoms to form corner-sharing SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 41–44°. There is two shorter (1.65 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 4-coordinate geometry to one Na1+, one Mg2+, and two Si4+ atoms. In the second O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+ and two Si4+ atoms. In the third O2- site, O2- is bonded in a 4-coordinate geometry to one Na1+, one Mg2+, and two Si4+ atoms. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to one Na1+, one Mg2+, and two Si4+ atoms. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+ and two Si4+ atoms. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to one Na1+, one Mg2+, and two Si4+ atoms.