Materials Data on CaCeMg6 by Materials Project

Abstract

CaMg6Ce crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. Ca is bonded to ten Mg and two equivalent Ce atoms to form distorted CaCe2Mg10 cuboctahedra that share corners with four equivalent CeCa2Mg10 cuboctahedra, corners with six equivalent CaCe2Mg10 cuboctahedra, edges with two equivalent CeCa2Mg10 cuboctahedra, faces with two equivalent CaCe2Mg10 cuboctahedra, and faces with two equivalent CeCa2Mg10 cuboctahedra. There are a spread of Ca–Mg bond distances ranging from 3.26–3.48 Å. Both Ca–Ce bond lengths are 3.71 Å. There are four inequivalent Mg sites. In the first Mg site, Mg is bonded in a 10-coordinate geometry to two equivalent Ca, six Mg, and two equivalent Ce atoms. There are a spread of Mg–Mg bond distances ranging from 3.26–3.36 Å. There are one shorter (3.28 Å) and one longer (3.47 Å) Mg–Ce bond lengths. In the second Mg site, Mg is bonded in a 9-coordinate geometry to two equivalent Ca, five Mg, and two equivalent Ce atoms. There are a spread of Mg–Mg bond distances ranging from 3.11–3.51 Å. Both Mg–Ce bond lengths are 3.32 Å. In the third Mg site, Mg is bonded in a 8-coordinate geometry to two equivalent Ca and six Mg atoms. In the fourth Mg site, Mg is bonded in a 10-coordinate geometry to eight Mg and two equivalent Ce atoms. Both Mg–Ce bond lengths are 3.47 Å. Ce is bonded to two equivalent Ca and ten Mg atoms to form distorted CeCa2Mg10 cuboctahedra that share corners with four equivalent CaCe2Mg10 cuboctahedra, corners with six equivalent CeCa2Mg10 cuboctahedra, edges with two equivalent CaCe2Mg10 cuboctahedra, faces with two equivalent CaCe2Mg10 cuboctahedra, and faces with two equivalent CeCa2Mg10 cuboctahedra.