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DOE OSTI · 1705673

Materials Data on U12Ge3Te20 by Materials Project

Abstract

U12Ge3Te20 crystallizes in the orthorhombic Pmm2 space group. The structure is three-dimensional. there are seven inequivalent U sites. In the first U site, U is bonded in a 9-coordinate geometry to two equivalent Ge and seven Te atoms. Both U–Ge bond lengths are 3.21 Å. There are a spread of U–Te bond distances ranging from 3.13–3.24 Å. In the second U site, U is bonded to seven Te atoms to form distorted edge-sharing UTe7 pentagonal bipyramids. There are a spread of U–Te bond distances ranging from 3.07–3.27 Å. In the third U site, U is bonded in a 9-coordinate geometry to two equivalent Ge and seven Te atoms. Both U–Ge bond lengths are 3.21 Å. There are a spread of U–Te bond distances ranging from 3.13–3.24 Å. In the fourth U site, U is bonded in a 8-coordinate geometry to eight Te atoms. There are a spread of U–Te bond distances ranging from 3.18–3.33 Å. In the fifth U site, U is bonded in a 9-coordinate geometry to one Ge and eight Te atoms. The U–Ge bond length is 3.22 Å. There are a spread of U–Te bond distances ranging from 3.17–3.30 Å. In the sixth U site, U is bonded in a 9-coordinate geometry to one Ge and eight Te atoms. The U–Ge bond length is 3.22 Å. There are a spread of U–Te bond distances ranging from 3.17–3.31 Å. In the seventh U site, U is bonded in a 9-coordinate geometry to one Ge and eight Te atoms. The U–Ge bond length is 3.21 Å. There are a spread of U–Te bond distances ranging from 3.17–3.36 Å. There are two inequivalent Ge sites. In the first Ge site, Ge is bonded to four U and four equivalent Te atoms to form distorted GeU4Te4 hexagonal bipyramids that share corners with twelve TeU5 trigonal bipyramids, edges with four TeU5 trigonal bipyramids, and faces with two equivalent GeU4Te4 hexagonal bipyramids. All Ge–Te bond lengths are 2.92 Å. In the second Ge site, Ge is bonded to four U and four Te atoms to form distorted GeU4Te4 hexagonal bipyramids that share corners with twelve TeU5 trigonal bipyramids, edges with four TeU5 trigonal bipyramids, and faces with two equivalent GeU4Te4 hexagonal bipyramids. There are two shorter (2.91 Å) and two longer (2.92 Å) Ge–Te bond lengths. There are eleven inequivalent Te sites. In the first Te site, Te is bonded to five U atoms to form a mixture of distorted edge and corner-sharing TeU5 trigonal bipyramids. In the second Te site, Te is bonded to five U atoms to form distorted TeU5 trigonal bipyramids that share corners with two equivalent GeU4Te4 hexagonal bipyramids, corners with four equivalent TeU5 trigonal bipyramids, edges with two equivalent GeU4Te4 hexagonal bipyramids, and edges with eight TeU5 trigonal bipyramids. In the third Te site, Te is bonded in a 6-coordinate geometry to four U and two equivalent Ge atoms. In the fourth Te site, Te is bonded in a 6-coordinate geometry to four U and two equivalent Ge atoms. In the fifth Te site, Te is bonded in a 4-coordinate geometry to four U atoms. In the sixth Te site, Te is bonded in a 6-coordinate geometry to four U and two equivalent Ge atoms. In the seventh Te site, Te is bonded to five U atoms to form distorted TeU5 trigonal bipyramids that share corners with two equivalent GeU4Te4 hexagonal bipyramids, corners with four TeU5 trigonal bipyramids, and edges with eight TeU5 trigonal bipyramids. In the eighth Te site, Te is bonded to five U atoms to form distorted TeU5 trigonal bipyramids that share corners with five GeU4Te4 hexagonal bipyramids, corners with four TeU5 trigonal bipyramids, an edgeedge with one GeU4Te4 hexagonal bipyramid, and edges with eight TeU5 trigonal bipyramids. In the ninth Te site, Te is bonded to five U atoms to form distorted TeU5 trigonal bipyramids that share corners with five GeU4Te4 hexagonal bipyramids, corners with four TeU5 trigonal bipyramids, an edgeedge with one GeU4Te4 hexagonal bipyramid, and edges with eight TeU5 trigonal bipyramids. In the tenth Te site, Te is bonded to five U atoms to form distorted TeU5 trigonal bipyramids that share corners with three equivalent GeU4Te4 hexagonal bipyramids, corners with four TeU5 trigonal bipyramids, an edgeedge with one GeU4Te4 hexagonal bipyramid, and edges with eight TeU5 trigonal bipyramids. In the eleventh Te site, Te is bonded to five U atoms to form distorted TeU5 trigonal bipyramids that share corners with two equivalent GeU4Te4 hexagonal bipyramids, corners with four TeU5 trigonal bipyramids, edges with two equivalent GeU4Te4 hexagonal bipyramids, and edges with eight TeU5 trigonal bipyramids.

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2020-04-29. Materials Data on U12Ge3Te20 by Materials Project. https://doi.org/10.17188/1705673

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