La2Mg crystallizes in the monoclinic C2/c space group. Mg(1) is bonded to two equivalent Mg(1) and ten La(1,1) atoms to form distorted MgLa10Mg2 cuboctahedra that share corners with six equivalent Mg(1)La10Mg2 cuboctahedra; corners with twelve equivalent La(1)La7Mg5 cuboctahedra; edges with eight La(1,1)La7Mg5 cuboctahedra; edges with ten equivalent Mg(1)La10Mg2 cuboctahedra; faces with four equivalent Mg(1)La10Mg2 cuboctahedra; and faces with sixteen La(1,1)La7Mg5 cuboctahedra. There are two inequivalent La sites. In the first La site, La(1) is bonded to five equivalent Mg(1) and seven La(1,1) atoms to form distorted LaLa7Mg5 cuboctahedra that share corners with six equivalent Mg(1)La10Mg2 cuboctahedra; corners with twelve La(1,1)La7Mg5 cuboctahedra; edges with four equivalent Mg(1)La10Mg2 cuboctahedra; edges with fourteen La(1,1)La7Mg5 cuboctahedra; faces with eight equivalent Mg(1)La10Mg2 cuboctahedra; and faces with twelve La(1,1)La7Mg5 cuboctahedra. In the second La site, La(1) is bonded to five equivalent Mg(1) and seven La(1,1) atoms to form distorted LaLa7Mg5 cuboctahedra that share corners with six equivalent Mg(1)La10Mg2 cuboctahedra; corners with twelve La(1,1)La7Mg5 cuboctahedra; edges with four equivalent Mg(1)La10Mg2 cuboctahedra; edges with fourteen La(1,1)La7Mg5 cuboctahedra; faces with eight equivalent Mg(1)La10Mg2 cuboctahedra; and faces with twelve La(1,1)La7Mg5 cuboctahedra.
La2Mg crystallizes in the monoclinic C2/c space group. Mg(1) is bonded to two equivalent Mg(1) and ten La(1,1) atoms to form distorted MgLa10Mg2 cuboctahedra that share corners with six equivalent Mg(1)La10Mg2 cuboctahedra; corners with twelve equivalent La(1)La7Mg5 cuboctahedra; edges with eight La(1,1)La7Mg5 cuboctahedra; edges with ten equivalent Mg(1)La10Mg2 cuboctahedra; faces with four equivalent Mg(1)La10Mg2 cuboctahedra; and faces with sixteen La(1,1)La7Mg5 cuboctahedra. Both Mg(1)-Mg(1) bond lengths are 3.50 Å. There are a spread of Mg(1)-La(1,1) bond distances ranging from 3.53-3.72 Å. There are two inequivalent La sites. In the first La site, La(1) is bonded to five equivalent Mg(1) and seven La(1,1) atoms to form distorted LaLa7Mg5 cuboctahedra that share corners with six equivalent Mg(1)La10Mg2 cuboctahedra; corners with twelve La(1,1)La7Mg5 cuboctahedra; edges with four equivalent Mg(1)La10Mg2 cuboctahedra; edges with fourteen La(1,1)La7Mg5 cuboctahedra; faces with eight equivalent Mg(1)La10Mg2 cuboctahedra; and faces with twelve La(1,1)La7Mg5 cuboctahedra. There are a spread of La(1)-La(1,1) bond distances ranging from 3.54-3.69 Å. In the second La site, La(1) is bonded to five equivalent Mg(1) and seven La(1,1) atoms to form distorted LaLa7Mg5 cuboctahedra that share corners with six equivalent Mg(1)La10Mg2 cuboctahedra; corners with twelve La(1,1)La7Mg5 cuboctahedra; edges with four equivalent Mg(1)La10Mg2 cuboctahedra; edges with fourteen La(1,1)La7Mg5 cuboctahedra; faces with eight equivalent Mg(1)La10Mg2 cuboctahedra; and faces with twelve La(1,1)La7Mg5 cuboctahedra. Both La(1)-La(1) bond lengths are 3.58 Å.