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DOE OSTI · 1207289

Materials Data on Ca(AlSe2)2 by Materials Project

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Abstract

Ca(AlSe2)2 crystallizes in the orthorhombic Cccm space group. The structure is three-dimensional. Ca2+ is bonded in a 8-coordinate geometry to eight Se2- atoms. There are four shorter (3.17 Å) and four longer (3.22 Å) Ca–Se bond lengths. Al3+ is bonded to four Se2- atoms to form edge-sharing AlSe4 tetrahedra. There are a spread of Al–Se bond distances ranging from 2.41–2.44 Å. There are two inequivalent Se2- sites. In the first Se2- site, Se2- is bonded to two equivalent Ca2+ and two equivalent Al3+ atoms to form a mixture of distorted edge and corner-sharing SeCa2Al2 trigonal pyramids. In the second Se2- site, Se2- is bonded in a 4-coordinate geometry to two equivalent Ca2+ and two equivalent Al3+ atoms.

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36 MATERIALS SCIENCEAl-Ca-SeCa(AlSe2)2crystal structure

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2020-05-09. Materials Data on Ca(AlSe2)2 by Materials Project. https://doi.org/10.17188/1207289

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