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DOE OSTI · 1279537

Materials Data on Y2Si4CN6 by Materials Project

Abstract

Y2Si4N6C crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are two inequivalent Y3+ sites. In the first Y3+ site, Y3+ is bonded to six N3- atoms to form distorted YN6 pentagonal pyramids that share corners with ten SiCN3 tetrahedra, an edgeedge with one YN6 pentagonal pyramid, and an edgeedge with one SiCN3 tetrahedra. There are a spread of Y–N bond distances ranging from 2.35–2.60 Å. In the second Y3+ site, Y3+ is bonded in a 6-coordinate geometry to six N3- atoms. There are a spread of Y–N bond distances ranging from 2.34–2.90 Å. There are four inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to one C4- and three N3- atoms to form SiCN3 tetrahedra that share corners with two equivalent YN6 pentagonal pyramids, corners with six SiCN3 tetrahedra, and an edgeedge with one YN6 pentagonal pyramid. The Si–C bond length is 1.91 Å. There is two shorter (1.75 Å) and one longer (1.77 Å) Si–N bond length. In the second Si4+ site, Si4+ is bonded to one C4- and three N3- atoms to form SiCN3 tetrahedra that share corners with three equivalent YN6 pentagonal pyramids and corners with six SiCN3 tetrahedra. The Si–C bond length is 1.91 Å. There are a spread of Si–N bond distances ranging from 1.73–1.76 Å. In the third Si4+ site, Si4+ is bonded to one C4- and three N3- atoms to form SiCN3 tetrahedra that share corners with two equivalent YN6 pentagonal pyramids and corners with six SiCN3 tetrahedra. The Si–C bond length is 1.92 Å. There is one shorter (1.74 Å) and two longer (1.76 Å) Si–N bond length. In the fourth Si4+ site, Si4+ is bonded to one C4- and three N3- atoms to form SiCN3 tetrahedra that share corners with three equivalent YN6 pentagonal pyramids and corners with six SiCN3 tetrahedra. The Si–C bond length is 1.88 Å. There is two shorter (1.75 Å) and one longer (1.76 Å) Si–N bond length. C4- is bonded to four Si4+ atoms to form CSi4 tetrahedra that share corners with six NY2Si2 tetrahedra and corners with four NY2Si2 trigonal pyramids. There are six inequivalent N3- sites. In the first N3- site, N3- is bonded to two Y3+ and two Si4+ atoms to form distorted NY2Si2 trigonal pyramids that share corners with two equivalent CSi4 tetrahedra, corners with six NY2Si2 tetrahedra, a cornercorner with one NY2Si2 trigonal pyramid, an edgeedge with one NY2Si2 tetrahedra, and an edgeedge with one NY2Si2 trigonal pyramid. In the second N3- site, N3- is bonded to two Y3+ and two Si4+ atoms to form distorted NY2Si2 trigonal pyramids that share corners with two equivalent CSi4 tetrahedra, corners with six NY2Si2 tetrahedra, a cornercorner with one NY2Si2 trigonal pyramid, an edgeedge with one NY2Si2 tetrahedra, and an edgeedge with one NY2Si2 trigonal pyramid. In the third N3- site, N3- is bonded to two Y3+ and two Si4+ atoms to form distorted NY2Si2 tetrahedra that share corners with two equivalent CSi4 tetrahedra, corners with six NY2Si2 tetrahedra, corners with three NY2Si2 trigonal pyramids, and an edgeedge with one NY2Si2 trigonal pyramid. In the fourth N3- site, N3- is bonded to two equivalent Y3+ and two Si4+ atoms to form distorted NY2Si2 tetrahedra that share corners with two equivalent CSi4 tetrahedra, corners with four NY2Si2 tetrahedra, corners with five NY2Si2 trigonal pyramids, and an edgeedge with one NY2Si2 tetrahedra. In the fifth N3- site, N3- is bonded in a 3-coordinate geometry to two Y3+ and two Si4+ atoms. In the sixth N3- site, N3- is bonded to two equivalent Y3+ and two Si4+ atoms to form distorted NY2Si2 tetrahedra that share corners with two equivalent CSi4 tetrahedra, corners with four NY2Si2 tetrahedra, corners with four NY2Si2 trigonal pyramids, an edgeedge with one NY2Si2 tetrahedra, and an edgeedge with one NY2Si2 trigonal pyramid.

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2020-07-15. Materials Data on Y2Si4CN6 by Materials Project. https://doi.org/10.17188/1279537

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