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DOE OSTI · 1685940

Materials Data on Sr2Li7CuN4 by Materials Project

Abstract

Li7Sr2CuN4 crystallizes in the orthorhombic Imm2 space group. The structure is three-dimensional. there are seven inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded in a trigonal planar geometry to three N3- atoms. There are one shorter (2.13 Å) and two longer (2.17 Å) Li–N bond lengths. In the second Li1+ site, Li1+ is bonded in a trigonal planar geometry to three N3- atoms. There are two shorter (2.10 Å) and one longer (2.16 Å) Li–N bond lengths. In the third Li1+ site, Li1+ is bonded in a trigonal planar geometry to three N3- atoms. All Li–N bond lengths are 2.16 Å. In the fourth Li1+ site, Li1+ is bonded in a trigonal planar geometry to three N3- atoms. There are two shorter (2.11 Å) and one longer (2.14 Å) Li–N bond lengths. In the fifth Li1+ site, Li1+ is bonded in a linear geometry to two equivalent N3- atoms. Both Li–N bond lengths are 1.93 Å. In the sixth Li1+ site, Li1+ is bonded in a linear geometry to two equivalent N3- atoms. Both Li–N bond lengths are 1.88 Å. In the seventh Li1+ site, Li1+ is bonded in a linear geometry to two equivalent N3- atoms. Both Li–N bond lengths are 1.93 Å. There are two inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded in a 4-coordinate geometry to four N3- atoms. There are two shorter (2.64 Å) and two longer (2.66 Å) Sr–N bond lengths. In the second Sr2+ site, Sr2+ is bonded in a 4-coordinate geometry to four N3- atoms. There are two shorter (2.63 Å) and two longer (2.69 Å) Sr–N bond lengths. Cu1+ is bonded in a linear geometry to two equivalent N3- atoms. Both Cu–N bond lengths are 1.87 Å. There are four inequivalent N3- sites. In the first N3- site, N3- is bonded to five Li1+ and two equivalent Sr2+ atoms to form a mixture of distorted edge and corner-sharing NSr2Li5 pentagonal bipyramids. In the second N3- site, N3- is bonded to three Li1+, two equivalent Sr2+, and two equivalent Cu1+ atoms to form a mixture of distorted edge and corner-sharing NSr2Li3Cu2 pentagonal bipyramids. In the third N3- site, N3- is bonded to five Li1+ and two equivalent Sr2+ atoms to form distorted NSr2Li5 pentagonal bipyramids that share corners with six NSr2Li3Cu2 pentagonal bipyramids and edges with four NSr2Li5 pentagonal bipyramids. In the fourth N3- site, N3- is bonded to five Li1+ and two equivalent Sr2+ atoms to form distorted NSr2Li5 pentagonal bipyramids that share corners with six NSr2Li5 pentagonal bipyramids and edges with four NSr2Li3Cu2 pentagonal bipyramids.

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2020-05-09. Materials Data on Sr2Li7CuN4 by Materials Project. https://doi.org/10.17188/1685940

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