Materials Data on Ca2Si5N8 by Materials Project

Abstract

Ca2Si5N8 crystallizes in the orthorhombic Pbca space group. The structure is three-dimensional. there are two inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded in a 7-coordinate geometry to seven N3- atoms. There are a spread of Ca–N bond distances ranging from 2.41–3.07 Å. In the second Ca2+ site, Ca2+ is bonded in a 6-coordinate geometry to six N3- atoms. There are a spread of Ca–N bond distances ranging from 2.41–3.08 Å. There are five inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to four N3- atoms to form corner-sharing SiN4 tetrahedra. There are a spread of Si–N bond distances ranging from 1.67–1.79 Å. In the second Si4+ site, Si4+ is bonded to four N3- atoms to form corner-sharing SiN4 tetrahedra. There are a spread of Si–N bond distances ranging from 1.71–1.77 Å. In the third Si4+ site, Si4+ is bonded to four N3- atoms to form corner-sharing SiN4 tetrahedra. There are a spread of Si–N bond distances ranging from 1.70–1.77 Å. In the fourth Si4+ site, Si4+ is bonded to four N3- atoms to form corner-sharing SiN4 tetrahedra. There are a spread of Si–N bond distances ranging from 1.70–1.79 Å. In the fifth Si4+ site, Si4+ is bonded to four N3- atoms to form corner-sharing SiN4 tetrahedra. There are a spread of Si–N bond distances ranging from 1.69–1.80 Å. There are eight inequivalent N3- sites. In the first N3- site, N3- is bonded in a distorted tetrahedral geometry to one Ca2+ and three Si4+ atoms. In the second N3- site, N3- is bonded in a 4-coordinate geometry to two equivalent Ca2+ and two Si4+ atoms. In the third N3- site, N3- is bonded in a rectangular see-saw-like geometry to two Ca2+ and two Si4+ atoms. In the fourth N3- site, N3- is bonded in a 2-coordinate geometry to three Ca2+ and two Si4+ atoms. In the fifth N3- site, N3- is bonded in a distorted trigonal non-coplanar geometry to one Ca2+ and three Si4+ atoms. In the sixth N3- site, N3- is bonded in a distorted rectangular see-saw-like geometry to two Ca2+ and two Si4+ atoms. In the seventh N3- site, N3- is bonded in a 3-coordinate geometry to one Ca2+ and three Si4+ atoms. In the eighth N3- site, N3- is bonded in a distorted trigonal planar geometry to one Ca2+ and three Si4+ atoms.