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DOE OSTI · 1204295

Materials Data on Tb4BBr6 by Materials Project

Abstract

Tb4BBr6 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. there are four inequivalent Tb sites. In the first Tb site, Tb is bonded to two equivalent B and four Br atoms to form a mixture of corner and edge-sharing TbB2Br4 octahedra. The corner-sharing octahedral tilt angles are 7°. There are one shorter (2.66 Å) and one longer (2.69 Å) Tb–B bond lengths. There are a spread of Tb–Br bond distances ranging from 2.91–3.01 Å. In the second Tb site, Tb is bonded to one B and five Br atoms to form a mixture of corner and edge-sharing TbBBr5 octahedra. The corner-sharing octahedra tilt angles range from 4–13°. The Tb–B bond length is 2.54 Å. There are a spread of Tb–Br bond distances ranging from 2.77–3.15 Å. In the third Tb site, Tb is bonded to two equivalent B and four Br atoms to form a mixture of corner and edge-sharing TbB2Br4 octahedra. The corner-sharing octahedra tilt angles range from 4–13°. There are one shorter (2.62 Å) and one longer (2.68 Å) Tb–B bond lengths. There are a spread of Tb–Br bond distances ranging from 2.89–3.09 Å. In the fourth Tb site, Tb is bonded to one B and five Br atoms to form a mixture of corner and edge-sharing TbBBr5 octahedra. The corner-sharing octahedra tilt angles range from 4–5°. The Tb–B bond length is 2.54 Å. There are a spread of Tb–Br bond distances ranging from 2.84–3.11 Å. B is bonded to six Tb atoms to form edge-sharing BTb6 octahedra. There are six inequivalent Br sites. In the first Br site, Br is bonded in an L-shaped geometry to two Tb atoms. In the second Br site, Br is bonded in a T-shaped geometry to three Tb atoms. In the third Br site, Br is bonded in a distorted T-shaped geometry to three Tb atoms. In the fourth Br site, Br is bonded in a distorted T-shaped geometry to three Tb atoms. In the fifth Br site, Br is bonded in a rectangular see-saw-like geometry to four Tb atoms. In the sixth Br site, Br is bonded in a distorted T-shaped geometry to three Tb atoms.

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2020-05-01. Materials Data on Tb4BBr6 by Materials Project. https://doi.org/10.17188/1204295

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36 MATERIALS SCIENCE↗