Materials Data on Eu(CdAs)2 by Materials Project

Abstract

Eu(CdAs)2 crystallizes in the trigonal P-3m1 space group. The structure is three-dimensional. Eu2+ is bonded to six equivalent As3- atoms to form EuAs6 octahedra that share corners with twelve equivalent CdAs4 tetrahedra, edges with six equivalent EuAs6 octahedra, and edges with six equivalent CdAs4 tetrahedra. All Eu–As bond lengths are 3.15 Å. Cd2+ is bonded to four equivalent As3- atoms to form CdAs4 tetrahedra that share corners with six equivalent EuAs6 octahedra, corners with six equivalent CdAs4 tetrahedra, edges with three equivalent EuAs6 octahedra, and edges with three equivalent CdAs4 tetrahedra. The corner-sharing octahedra tilt angles range from 15–56°. There are three shorter (2.75 Å) and one longer (2.86 Å) Cd–As bond lengths. As3- is bonded to three equivalent Eu2+ and four equivalent Cd2+ atoms to form a mixture of distorted edge and corner-sharing AsEu3Cd4 pentagonal bipyramids.