Materials Data on CsMg6Nb by Materials Project

CsMg6Nb crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. Cs is bonded to twelve Mg atoms to form CsMg12 cuboctahedra that share corners with four equivalent CsMg12 cuboctahedra, edges with eight equivalent MgCs2Mg8Nb2 cuboctahedra, faces with two equivalent CsMg12 cuboctahedra, and faces with four equivalent MgCs2Mg8Nb2 cuboctahedra. There are a spread of Cs–Mg bond distances ranging from 3.59–3.63 Å. There are four inequivalent Mg sites. In the first Mg site, Mg is bonded to two equivalent Cs, eight Mg, and two equivalent Nb atoms to form MgCs2Mg8Nb2 cuboctahedra that share corners with twelve equivalent MgCs2Mg8Nb2 cuboctahedra, edges with four equivalent CsMg12 cuboctahedra, faces with two equivalent CsMg12 cuboctahedra, and faces with six equivalent MgCs2Mg8Nb2 cuboctahedra. There are four shorter (3.30 Å) and four longer (3.32 Å) Mg–Mg bond lengths. There are one shorter (3.57 Å) and one longer (3.62 Å) Mg–Nb bond lengths. In the second Mg site, Mg is bonded in a 10-coordinate geometry to two equivalent Cs, six Mg, and two equivalent Nb atoms. There are one shorter (2.97 Å) and one longer (2.98 Å) Mg–Mg bond lengths. Both Mg–Nb bond lengths are 2.95 Å. In the third Mg site, Mg is bonded in a 10-coordinate geometry to two equivalent Cs, six Mg, and two equivalent Nb atoms. Both Mg–Nb bond lengths are 2.96 Å. In the fourth Mg site, Mg is bonded in a 10-coordinate geometry to two equivalent Cs, six Mg, and two equivalent Nb atoms. Both Mg–Nb bond lengths are 2.95 Å. Nb is bonded in a 12-coordinate geometry to twelve Mg atoms.