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DOE OSTI · 1720791

Materials Data on KSi5N7 by Materials Project

Abstract

KSi5N7 crystallizes in the orthorhombic Pna2_1 space group. The structure is three-dimensional. there are two inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 5-coordinate geometry to five N3- atoms. There are a spread of K–N bond distances ranging from 2.58–2.79 Å. In the second K1+ site, K1+ is bonded in a 12-coordinate geometry to nine N3- atoms. There are a spread of K–N bond distances ranging from 2.71–3.24 Å. There are ten inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to four N3- atoms to form a mixture of distorted edge and corner-sharing SiN4 tetrahedra. There are a spread of Si–N bond distances ranging from 1.74–1.76 Å. In the second Si4+ site, Si4+ is bonded to four N3- atoms to form a mixture of distorted edge and corner-sharing SiN4 tetrahedra. There are a spread of Si–N bond distances ranging from 1.73–1.75 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 1.73–1.76 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 1.73–1.77 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 1.68–1.83 Å. In the sixth 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 1.74–1.77 Å. In the seventh 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 1.65–1.79 Å. In the eighth 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 1.67–1.82 Å. In the ninth 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 1.66–1.80 Å. In the tenth 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 1.73–1.79 Å. There are fourteen inequivalent N3- sites. In the first N3- site, N3- is bonded to one K1+ and three Si4+ atoms to form distorted corner-sharing NKSi3 tetrahedra. In the second N3- site, N3- is bonded in a 3-coordinate geometry to one K1+ and three Si4+ atoms. In the third N3- site, N3- is bonded in a distorted trigonal planar geometry to one K1+ and three Si4+ atoms. In the fourth N3- site, N3- is bonded in a distorted T-shaped geometry to three Si4+ atoms. In the fifth N3- site, N3- is bonded in a trigonal planar geometry to one K1+ and three Si4+ atoms. In the sixth N3- site, N3- is bonded in a trigonal planar geometry to one K1+ and three Si4+ atoms. In the seventh N3- site, N3- is bonded to one K1+ and three Si4+ atoms to form distorted corner-sharing NKSi3 trigonal pyramids. In the eighth N3- site, N3- is bonded in a distorted rectangular see-saw-like geometry to one K1+ and three Si4+ atoms. In the ninth N3- site, N3- is bonded in a trigonal planar geometry to three Si4+ atoms. In the tenth N3- site, N3- is bonded to one K1+ and three Si4+ atoms to form distorted corner-sharing NKSi3 trigonal pyramids. In the eleventh N3- site, N3- is bonded in a distorted trigonal planar geometry to one K1+ and three Si4+ atoms. In the twelfth N3- site, N3- is bonded in a 2-coordinate geometry to two equivalent K1+ and two Si4+ atoms. In the thirteenth N3- site, N3- is bonded in a 2-coordinate geometry to two equivalent K1+ and two Si4+ atoms. In the fourteenth N3- site, N3- is bonded in a distorted trigonal planar geometry to one K1+ and three Si4+ atoms.

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2020-04-29. Materials Data on KSi5N7 by Materials Project. https://doi.org/10.17188/1720791

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