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DOE OSTI · 1191423

Materials Data on RbScAsO4F by Materials Project

Abstract

RbScAsO4F crystallizes in the orthorhombic Pna2_1 space group. The structure is three-dimensional. there are two inequivalent Rb1+ sites. In the first Rb1+ site, Rb1+ is bonded in a 9-coordinate geometry to seven O2- and two F1- atoms. There are a spread of Rb–O bond distances ranging from 2.89–3.33 Å. There are one shorter (2.95 Å) and one longer (3.35 Å) Rb–F bond lengths. In the second Rb1+ site, Rb1+ is bonded in a 8-coordinate geometry to six O2- and two F1- atoms. There are a spread of Rb–O bond distances ranging from 2.89–3.31 Å. There are one shorter (2.93 Å) and one longer (3.24 Å) Rb–F bond lengths. There are two inequivalent Sc3+ sites. In the first Sc3+ site, Sc3+ is bonded to four O2- and two F1- atoms to form ScO4F2 octahedra that share corners with two equivalent ScO4F2 octahedra and corners with four AsO4 tetrahedra. The corner-sharing octahedral tilt angles are 48°. There are a spread of Sc–O bond distances ranging from 2.03–2.14 Å. There are one shorter (2.12 Å) and one longer (2.15 Å) Sc–F bond lengths. In the second Sc3+ site, Sc3+ is bonded to four O2- and two F1- atoms to form ScO4F2 octahedra that share corners with two equivalent ScO4F2 octahedra and corners with four AsO4 tetrahedra. The corner-sharing octahedral tilt angles are 48°. There are a spread of Sc–O bond distances ranging from 2.08–2.16 Å. There are one shorter (2.07 Å) and one longer (2.10 Å) Sc–F bond lengths. There are two inequivalent As5+ sites. In the first As5+ site, As5+ is bonded to four O2- atoms to form AsO4 tetrahedra that share corners with four ScO4F2 octahedra. The corner-sharing octahedra tilt angles range from 40–50°. There are a spread of As–O bond distances ranging from 1.71–1.73 Å. In the second As5+ site, As5+ is bonded to four O2- atoms to form AsO4 tetrahedra that share corners with four ScO4F2 octahedra. The corner-sharing octahedra tilt angles range from 45–49°. There is one shorter (1.71 Å) and three longer (1.72 Å) As–O bond length. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to two Rb1+, one Sc3+, and one As5+ atom. In the second O2- site, O2- is bonded in a bent 150 degrees geometry to one Sc3+ and one As5+ atom. In the third O2- site, O2- is bonded in a 2-coordinate geometry to two Rb1+, one Sc3+, and one As5+ atom. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to two Rb1+, one Sc3+, and one As5+ atom. In the fifth O2- site, O2- is bonded in a 2-coordinate geometry to two Rb1+, one Sc3+, and one As5+ atom. In the sixth O2- site, O2- is bonded in a 2-coordinate geometry to two Rb1+, one Sc3+, and one As5+ atom. In the seventh O2- site, O2- is bonded in a 2-coordinate geometry to one Rb1+, one Sc3+, and one As5+ atom. In the eighth O2- site, O2- is bonded in a 2-coordinate geometry to two Rb1+, one Sc3+, and one As5+ atom. There are two inequivalent F1- sites. In the first F1- site, F1- is bonded in a 2-coordinate geometry to two Rb1+ and two Sc3+ atoms. In the second F1- site, F1- is bonded in a 2-coordinate geometry to two Rb1+ and two Sc3+ atoms.

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2020-07-15. Materials Data on RbScAsO4F by Materials Project. https://doi.org/10.17188/1191423

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36 MATERIALS SCIENCE↗