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DOE OSTI · 1749375

Materials Data on Ca2P7Ir12 by Materials Project

Abstract

Ca2Ir12P7 crystallizes in the trigonal P-3 space group. The structure is three-dimensional. Ca is bonded to twelve Ir and six equivalent P atoms to form distorted CaP6Ir12 cuboctahedra that share corners with three equivalent PIr6 octahedra, edges with six equivalent CaP6Ir12 cuboctahedra, and faces with two equivalent CaP6Ir12 cuboctahedra. The corner-sharing octahedral tilt angles are 27°. There are a spread of Ca–Ir bond distances ranging from 3.08–3.41 Å. There are three shorter (3.00 Å) and three longer (3.02 Å) Ca–P bond lengths. There are two inequivalent Ir sites. In the first Ir site, Ir is bonded in a 4-coordinate geometry to one Ca, three equivalent Ir, and four P atoms. There are a spread of Ir–Ir bond distances ranging from 2.81–2.91 Å. There are a spread of Ir–P bond distances ranging from 2.32–2.58 Å. In the second Ir site, Ir is bonded in a 12-coordinate geometry to three equivalent Ca, five Ir, and four equivalent P atoms. Both Ir–Ir bond lengths are 2.77 Å. There are a spread of Ir–P bond distances ranging from 2.31–2.62 Å. There are two inequivalent P sites. In the first P site, P is bonded to six equivalent Ir atoms to form distorted PIr6 octahedra that share corners with six equivalent CaP6Ir12 cuboctahedra. In the second P site, P is bonded in a 9-coordinate geometry to two equivalent Ca and seven Ir atoms.

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2020-04-29. Materials Data on Ca2P7Ir12 by Materials Project. https://doi.org/10.17188/1749375

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36 MATERIALS SCIENCE↗