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DOE OSTI · 1748932

Materials Data on Tm2Si9B36C by Materials Project

Abstract

Tm2B36Si7C(Si)2 crystallizes in the monoclinic Cm space group. The structure is three-dimensional and consists of four silicon molecules and one Tm2B36Si7C framework. In the Tm2B36Si7C framework, Tm3+ is bonded to twelve B+0.83- atoms to form corner-sharing TmB12 cuboctahedra. There are a spread of Tm–B bond distances ranging from 2.75–2.96 Å. There are twenty inequivalent B+0.83- sites. In the first B+0.83- site, B+0.83- is bonded in a 6-coordinate geometry to six B+0.83- atoms. There are a spread of B–B bond distances ranging from 1.75–1.83 Å. In the second B+0.83- site, B+0.83- is bonded in a 7-coordinate geometry to one Tm3+ and six B+0.83- atoms. There are a spread of B–B bond distances ranging from 1.78–1.82 Å. In the third B+0.83- site, B+0.83- is bonded in a 7-coordinate geometry to one Tm3+ and six B+0.83- atoms. There is two shorter (1.81 Å) and three longer (1.82 Å) B–B bond length. In the fourth B+0.83- site, B+0.83- is bonded in a 6-coordinate geometry to six B+0.83- atoms. There are a spread of B–B bond distances ranging from 1.69–1.82 Å. In the fifth B+0.83- site, B+0.83- is bonded in a 7-coordinate geometry to one Tm3+ and six B+0.83- atoms. There are a spread of B–B bond distances ranging from 1.72–1.83 Å. In the sixth B+0.83- site, B+0.83- is bonded in a 7-coordinate geometry to one Tm3+ and six B+0.83- atoms. There are a spread of B–B bond distances ranging from 1.78–1.82 Å. In the seventh B+0.83- site, B+0.83- is bonded in a 6-coordinate geometry to five B+0.83- and one Si+3.11+ atom. There is one shorter (1.74 Å) and two longer (1.75 Å) B–B bond length. The B–Si bond length is 1.95 Å. In the eighth B+0.83- site, B+0.83- is bonded in a 1-coordinate geometry to five B+0.83- and one Si+3.11+ atom. There is one shorter (1.75 Å) and two longer (1.77 Å) B–B bond length. The B–Si bond length is 1.95 Å. In the ninth B+0.83- site, B+0.83- is bonded in a distorted single-bond geometry to five B+0.83- and one C4- atom. There are a spread of B–B bond distances ranging from 1.79–1.87 Å. The B–C bond length is 1.63 Å. In the tenth B+0.83- site, B+0.83- is bonded in a distorted single-bond geometry to five B+0.83- and one C4- atom. There is two shorter (1.82 Å) and one longer (1.87 Å) B–B bond length. The B–C bond length is 1.62 Å. In the eleventh B+0.83- site, B+0.83- is bonded in a 1-coordinate geometry to one Tm3+, five B+0.83-, and one Si+3.11+ atom. There is one shorter (1.77 Å) and one longer (1.81 Å) B–B bond length. The B–Si bond length is 2.05 Å. In the twelfth B+0.83- site, B+0.83- is bonded in a 6-coordinate geometry to five B+0.83- and one Si+3.11+ atom. There is one shorter (1.78 Å) and one longer (1.80 Å) B–B bond length. The B–Si bond length is 2.02 Å. In the thirteenth B+0.83- site, B+0.83- is bonded in a 1-coordinate geometry to one Tm3+, five B+0.83-, and one Si+3.11+ atom. There is one shorter (1.80 Å) and one longer (1.82 Å) B–B bond length. The B–Si bond length is 2.09 Å. In the fourteenth B+0.83- site, B+0.83- is bonded in a 1-coordinate geometry to one Tm3+, five B+0.83-, and one Si+3.11+ atom. The B–B bond length is 1.79 Å. The B–Si bond length is 2.04 Å. In the fifteenth B+0.83- site, B+0.83- is bonded in a 1-coordinate geometry to five B+0.83- and one Si+3.11+ atom. The B–B bond length is 1.78 Å. The B–Si bond length is 2.01 Å. In the sixteenth B+0.83- site, B+0.83- is bonded in a 1-coordinate geometry to one Tm3+, five B+0.83-, and one Si+3.11+ atom. The B–B bond length is 1.80 Å. The B–Si bond length is 2.08 Å. In the seventeenth B+0.83- site, B+0.83- is bonded in a 1-coordinate geometry to one Tm3+, five B+0.83-, and one Si+3.11+ atom. The B–Si bond length is 2.04 Å. In the eighteenth B+0.83- site, B+0.83- is bonded in a 1-coordinate geometry to two equivalent Tm3+, five B+0.83-, and one Si+3.11+ atom. The B–Si bond length is 2.10 Å. In the nineteenth B+0.83- site, B+0.83- is bonded in a 1-coordinate geometry to one Tm3+, five B+0.83-, and one Si+3.11+ atom. The B–Si bond length is 2.05 Å. In the twentieth B+0.83- site, B+0.83- is bonded in a 1-coordinate geometry to two equivalent Tm3+, five B+0.83-, and one Si+3.11+ atom. The B–Si bond length is 2.10 Å. There are five inequivalent Si+3.11+ sites. In the first Si+3.11+ site, Si+3.11+ is bonded in a trigonal non-coplanar geometry to three B+0.83- atoms. In the second Si+3.11+ site, Si+3.11+ is bonded in a trigonal non-coplanar geometry to three B+0.83- atoms. In the third Si+3.11+ site, Si+3.11+ is bonded in a trigonal non-coplanar geometry to three B+0.83- atoms. In the fourth Si+3.11+ site, Si+3.11+ is bonded in a trigonal non-coplanar geometry to three B+0.83- atoms. In the fifth Si+3.11+ site, Si+3.11+ is bonded in a distorted tetrahedral geometry to three B+0.83- and one C4- atom. The Si–C bond length is 1.84 Å. C4- is bonded in a tetrahedral geometry to three B+0.83- and one Si+3.11+ atom.

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2020-04-30. Materials Data on Tm2Si9B36C by Materials Project. https://doi.org/10.17188/1748932

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