Materials Data on SrYMg6 by Materials Project
SrMg6Y crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. Sr is bonded to twelve Mg atoms to form SrMg12 cuboctahedra that share corners with four equivalent SrMg12 cuboctahedra, corners with eight equivalent YMg12 cuboctahedra, edges with eight equivalent MgSr2Y2Mg8 cuboctahedra, faces with two equivalent SrMg12 cuboctahedra, faces with four equivalent MgSr2Y2Mg8 cuboctahedra, and faces with four equivalent YMg12 cuboctahedra. There are a spread of Sr–Mg bond distances ranging from 3.38–3.50 Å. There are four inequivalent Mg sites. In the first Mg site, Mg is bonded to two equivalent Sr, eight Mg, and two equivalent Y atoms to form distorted MgSr2Y2Mg8 cuboctahedra that share corners with twelve equivalent MgSr2Y2Mg8 cuboctahedra, edges with four equivalent SrMg12 cuboctahedra, edges with four equivalent YMg12 cuboctahedra, faces with two equivalent SrMg12 cuboctahedra, faces with two equivalent YMg12 cuboctahedra, and faces with six equivalent MgSr2Y2Mg8 cuboctahedra. There are six shorter (3.40 Å) and two longer (3.41 Å) Mg–Mg bond lengths. There are one shorter (3.37 Å) and one longer (3.38 Å) Mg–Y bond lengths. In the second Mg site, Mg is bonded in a 12-coordinate geometry to two equivalent Sr, eight Mg, and two equivalent Y atoms. There are a spread of Mg–Mg bond distances ranging from 3.20–3.56 Å. Both Mg–Y bond lengths are 3.32 Å. In the third Mg site, Mg is bonded in a 12-coordinate geometry to two equivalent Sr, eight Mg, and two equivalent Y atoms. Both Mg–Y bond lengths are 3.32 Å. In the fourth Mg site, Mg is bonded in a 12-coordinate geometry to two equivalent Sr, eight Mg, and two equivalent Y atoms. Both Mg–Y bond lengths are 3.31 Å. Y is bonded to twelve Mg atoms to form YMg12 cuboctahedra that share corners with four equivalent YMg12 cuboctahedra, corners with eight equivalent SrMg12 cuboctahedra, edges with eight equivalent MgSr2Y2Mg8 cuboctahedra, faces with two equivalent YMg12 cuboctahedra, faces with four equivalent SrMg12 cuboctahedra, and faces with four equivalent MgSr2Y2Mg8 cuboctahedra.