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DOE OSTI · 1681351

Materials Data on Rb4Sn21Hg2 by Materials Project

Abstract

Rb4Hg2Sn21 crystallizes in the orthorhombic Ama2 space group. The structure is three-dimensional. there are four inequivalent Rb sites. In the first Rb site, Rb is bonded in a 8-coordinate geometry to twenty Sn atoms. There are a spread of Rb–Sn bond distances ranging from 3.93–4.17 Å. In the second Rb site, Rb is bonded in a 8-coordinate geometry to eight Sn atoms. There are a spread of Rb–Sn bond distances ranging from 4.18–4.23 Å. In the third Rb site, Rb is bonded in a 8-coordinate geometry to eight Sn atoms. There are a spread of Rb–Sn bond distances ranging from 4.19–4.25 Å. In the fourth Rb site, Rb is bonded in a 8-coordinate geometry to eight Sn atoms. There are a spread of Rb–Sn bond distances ranging from 4.18–4.24 Å. There are two inequivalent Hg sites. In the first Hg site, Hg is bonded to four Sn atoms to form HgSn4 tetrahedra that share corners with six SnRbSn4 trigonal bipyramids. There are two shorter (2.89 Å) and two longer (2.90 Å) Hg–Sn bond lengths. In the second Hg site, Hg is bonded to four Sn atoms to form HgSn4 tetrahedra that share corners with eight SnRbSn4 trigonal bipyramids. All Hg–Sn bond lengths are 2.87 Å. There are thirteen inequivalent Sn sites. In the first Sn site, Sn is bonded in a 5-coordinate geometry to one Rb and four Sn atoms. There are three shorter (2.88 Å) and one longer (2.90 Å) Sn–Sn bond lengths. In the second Sn site, Sn is bonded to one Rb and four Sn atoms to form distorted SnRbSn4 trigonal bipyramids that share corners with three HgSn4 tetrahedra, corners with two SnRbSn4 trigonal bipyramids, and edges with three SnRbSn4 trigonal bipyramids. There are a spread of Sn–Sn bond distances ranging from 2.88–2.96 Å. In the third Sn site, Sn is bonded to one Rb and four Sn atoms to form distorted SnRbSn4 trigonal bipyramids that share a cornercorner with one SnSn4 tetrahedra, corners with two HgSn4 tetrahedra, corners with three SnRbSn4 trigonal bipyramids, and edges with two SnRbSn4 trigonal bipyramids. There are a spread of Sn–Sn bond distances ranging from 2.87–2.93 Å. In the fourth Sn site, Sn is bonded to one Rb and four Sn atoms to form distorted SnRbSn4 trigonal bipyramids that share a cornercorner with one SnSn4 tetrahedra, corners with two HgSn4 tetrahedra, corners with three SnRbSn4 trigonal bipyramids, and edges with two SnRbSn4 trigonal bipyramids. There are one shorter (2.87 Å) and two longer (2.89 Å) Sn–Sn bond lengths. In the fifth Sn site, Sn is bonded in a 7-coordinate geometry to three Rb and four Sn atoms. There are one shorter (2.95 Å) and one longer (2.98 Å) Sn–Sn bond lengths. In the sixth Sn site, Sn is bonded in a 7-coordinate geometry to three Rb and four Sn atoms. There are one shorter (2.95 Å) and one longer (2.97 Å) Sn–Sn bond lengths. In the seventh Sn site, Sn is bonded in a 7-coordinate geometry to three Rb, one Hg, and three Sn atoms. The Sn–Sn bond length is 2.98 Å. In the eighth Sn site, Sn is bonded in a 4-coordinate geometry to three Rb, one Hg, and three Sn atoms. In the ninth Sn site, Sn is bonded in a 7-coordinate geometry to three Rb, one Hg, and three Sn atoms. The Sn–Sn bond length is 2.96 Å. In the tenth Sn site, Sn is bonded in a 7-coordinate geometry to three Rb, one Hg, and three Sn atoms. The Sn–Sn bond length is 2.97 Å. In the eleventh Sn site, Sn is bonded in a 7-coordinate geometry to three Rb and four Sn atoms. The Sn–Sn bond length is 2.95 Å. In the twelfth Sn site, Sn is bonded in a 4-coordinate geometry to three Rb, one Hg, and three Sn atoms. In the thirteenth Sn site, Sn is bonded to four Sn atoms to form corner-sharing SnSn4 tetrahedra.

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2020-04-30. Materials Data on Rb4Sn21Hg2 by Materials Project. https://doi.org/10.17188/1681351

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