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DOE OSTI · 1727037

Materials Data on MnCr4CdSe8 by Materials Project

Abstract

Cr4MnCdSe8 is Spinel-derived structured and crystallizes in the cubic F-43m space group. The structure is three-dimensional. Cr3+ is bonded to six Se2- atoms to form CrSe6 octahedra that share corners with three equivalent MnSe4 tetrahedra, corners with three equivalent CdSe4 tetrahedra, and edges with six equivalent CrSe6 octahedra. There are three shorter (2.54 Å) and three longer (2.58 Å) Cr–Se bond lengths. Mn2+ is bonded to four equivalent Se2- atoms to form MnSe4 tetrahedra that share corners with twelve equivalent CrSe6 octahedra. The corner-sharing octahedral tilt angles are 58°. All Mn–Se bond lengths are 2.54 Å. Cd2+ is bonded to four equivalent Se2- atoms to form CdSe4 tetrahedra that share corners with twelve equivalent CrSe6 octahedra. The corner-sharing octahedral tilt angles are 60°. All Cd–Se bond lengths are 2.63 Å. There are two inequivalent Se2- sites. In the first Se2- site, Se2- is bonded to three equivalent Cr3+ and one Cd2+ atom to form distorted SeCr3Cd tetrahedra that share corners with three equivalent SeCr3Cd tetrahedra, corners with nine equivalent SeMnCr3 trigonal pyramids, and edges with three equivalent SeCr3Cd tetrahedra. In the second Se2- site, Se2- is bonded to three equivalent Cr3+ and one Mn2+ atom to form distorted SeMnCr3 trigonal pyramids that share corners with nine equivalent SeCr3Cd tetrahedra, corners with three equivalent SeMnCr3 trigonal pyramids, and edges with three equivalent SeMnCr3 trigonal pyramids.

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2020-05-09. Materials Data on MnCr4CdSe8 by Materials Project. https://doi.org/10.17188/1727037

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