Materials Data on AcMg5 by Materials Project
Mg5Ac crystallizes in the hexagonal P-62m space group. The structure is three-dimensional. there are four inequivalent Mg sites. In the first Mg site, Mg is bonded to eight Mg and four equivalent Ac atoms to form a mixture of distorted edge, face, and corner-sharing MgAc4Mg8 cuboctahedra. There are four shorter (3.07 Å) and four longer (3.08 Å) Mg–Mg bond lengths. There are two shorter (3.91 Å) and two longer (4.03 Å) Mg–Ac bond lengths. In the second Mg site, Mg is bonded in a 9-coordinate geometry to six Mg and three equivalent Ac atoms. All Mg–Mg bond lengths are 3.07 Å. All Mg–Ac bond lengths are 3.56 Å. In the third Mg site, Mg is bonded to eight Mg and four equivalent Ac atoms to form a mixture of distorted edge, face, and corner-sharing MgAc4Mg8 cuboctahedra. Both Mg–Mg bond lengths are 3.08 Å. There are two shorter (3.91 Å) and two longer (4.03 Å) Mg–Ac bond lengths. In the fourth Mg site, Mg is bonded to eight Mg and four equivalent Ac atoms to form a mixture of distorted edge, face, and corner-sharing MgAc4Mg8 cuboctahedra. There are two shorter (3.91 Å) and two longer (4.03 Å) Mg–Ac bond lengths. Ac is bonded in a 6-coordinate geometry to eighteen Mg atoms.