LiMg6Si is beta Cu3Ti-derived structured and crystallizes in the orthorhombic Amm2 space group. Li(1) is bonded to two equivalent Mg(2), four equivalent Mg(1), four equivalent Mg(3), and two equivalent Si(1) atoms to form LiMg10Si2 cuboctahedra that share corners with four equivalent Mg(2)Li2Mg10 cuboctahedra, corners with six equivalent Li(1)Mg10Si2 cuboctahedra, corners with eight equivalent Mg(1)Li2Mg8Si2 cuboctahedra, edges with two equivalent Mg(2)Li2Mg10 cuboctahedra, edges with four equivalent Mg(1)Li2Mg8Si2 cuboctahedra, edges with four equivalent Si(1)Li2Mg10 cuboctahedra, edges with eight equivalent Mg(3)Li2Mg8Si2 cuboctahedra, faces with two equivalent Li(1)Mg10Si2 cuboctahedra, faces with two equivalent Mg(2)Li2Mg10 cuboctahedra, faces with two equivalent Si(1)Li2Mg10 cuboctahedra, faces with four equivalent Mg(1)Li2Mg8Si2 cuboctahedra, faces with four equivalent Mg(3)Li2Mg8Si2 cuboctahedra, and faces with six equivalent Mg(4)Mg10Si2 cuboctahedra. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent Li(1), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), and two equivalent Si(1) atoms to form distorted MgLi2Mg8Si2 cuboctahedra that share corners with four equivalent Li(1)Mg10Si2 cuboctahedra, corners with four equivalent Mg(2)Li2Mg10 cuboctahedra, corners with ten equivalent Mg(1)Li2Mg8Si2 cuboctahedra, edges with two equivalent Li(1)Mg10Si2 cuboctahedra, edges with two equivalent Mg(2)Li2Mg10 cuboctahedra, edges with two equivalent Mg(1)Li2Mg8Si2 cuboctahedra, edges with four equivalent Mg(3)Li2Mg8Si2 cuboctahedra, edges with four equivalent Mg(4)Mg10Si2 cuboctahedra, edges with four equivalent Si(1)Li2Mg10 cuboctahedra, faces with two equivalent Li(1)Mg10Si2 cuboctahedra, faces with two equivalent Mg(2)Li2Mg10 cuboctahedra, faces with two equivalent Mg(4)Mg10Si2 cuboctahedra, faces with two equivalent Si(1)Li2Mg10 cuboctahedra, faces with four equivalent Mg(1)Li2Mg8Si2 cuboctahedra, and faces with eight equivalent Mg(3)Li2Mg8Si2 cuboctahedra. In the second Mg site, Mg(2) is bonded to two equivalent Li(1), two equivalent Mg(4), four equivalent Mg(1), and four equivalent Mg(3) atoms to form MgLi2Mg10 cuboctahedra that share corners with four equivalent Li(1)Mg10Si2 cuboctahedra, corners with six equivalent Mg(2)Li2Mg10 cuboctahedra, corners with eight equivalent Mg(1)Li2Mg8Si2 cuboctahedra, edges with two equivalent Li(1)Mg10Si2 cuboctahedra, edges with four equivalent Mg(1)Li2Mg8Si2 cuboctahedra, edges with four equivalent Mg(4)Mg10Si2 cuboctahedra, edges with eight equivalent Mg(3)Li2Mg8Si2 cuboctahedra, faces with two equivalent Li(1)Mg10Si2 cuboctahedra, faces with two equivalent Mg(2)Li2Mg10 cuboctahedra, faces with two equivalent Mg(4)Mg10Si2 cuboctahedra, faces with four equivalent Mg(1)Li2Mg8Si2 cuboctahedra, faces with four equivalent Mg(3)Li2Mg8Si2 cuboctahedra, and faces with six equivalent Si(1)Li2Mg10 cuboctahedra. In the third Mg site, Mg(3) is bonded to two equivalent Li(1), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), and two equivalent Si(1) atoms to form distorted MgLi2Mg8Si2 cuboctahedra that share corners with four equivalent Mg(4)Mg10Si2 cuboctahedra, corners with four equivalent Si(1)Li2Mg10 cuboctahedra, corners with ten equivalent Mg(3)Li2Mg8Si2 cuboctahedra, edges with two equivalent Mg(3)Li2Mg8Si2 cuboctahedra, edges with two equivalent Mg(4)Mg10Si2 cuboctahedra, edges with two equivalent Si(1)Li2Mg10 cuboctahedra, edges with four equivalent Li(1)Mg10Si2 cuboctahedra, edges with four equivalent Mg(2)Li2Mg10 cuboctahedra, edges with four equivalent Mg(1)Li2Mg8Si2 cuboctahedra, faces with two equivalent Li(1)Mg10Si2 cuboctahedra, faces with two equivalent Mg(2)Li2Mg10 cuboctahedra, faces with two equivalent Mg(4)Mg10Si2 cuboctahedra, faces with two equivalent Si(1)Li2Mg10 cuboctahedra, faces with four equivalent Mg(3)Li2Mg8Si2 cuboctahedra, and faces with eight equivalent Mg(1)Li2Mg8Si2 cuboctahedra. In the fourth Mg site, Mg(4) is bonded to two equivalent Mg(2), four equivalent Mg(1), four equivalent Mg(3), and two equivalent Si(1) atoms to form distorted MgMg10Si2 cuboctahedra that share corners with four equivalent Si(1)Li2Mg10 cuboctahedra, corners with six equivalent Mg(4)Mg10Si2 cuboctahedra, corners with eight equivalent Mg(3)Li2Mg8Si2 cuboctahedra, edges with two equivalent Si(1)Li2Mg10 cuboctahedra, edges with four equivalent Mg(2)Li2Mg10 cuboctahedra, edges with four equivalent Mg(3)Li2Mg8Si2 cuboctahedra, edges with eight equivalent Mg(1)Li2Mg8Si2 cuboctahedra, faces with two equivalent Mg(2)Li2Mg10 cuboctahedra, faces with two equivalent Mg(4)Mg10Si2 cuboctahedra, faces with two equivalent Si(1)Li2Mg10 cuboctahedra, faces with four equivalent Mg(1)Li2Mg8Si2 cuboctahedra, faces with four equivalent Mg(3)Li2Mg8Si2 cuboctahedra, and faces with six equivalent Li(1)Mg10Si2 cuboctahedra. Si(1) is bonded to two equivalent Li(1), two equivalent Mg(4), four equivalent Mg(1), and four equivalent Mg(3) atoms to form SiLi2Mg10 cuboctahedra that share corners with four equivalent Mg(4)Mg10Si2 cuboctahedra, corners with six equivalent Si(1)Li2Mg10 cuboctahedra, corners with eight equivalent Mg(3)Li2Mg8Si2 cuboctahedra, edges with two equivalent Mg(4)Mg10Si2 cuboctahedra, edges with four equivalent Li(1)Mg10Si2 cuboctahedra, edges with four equivalent Mg(3)Li2Mg8Si2 cuboctahedra, edges with eight equivalent Mg(1)Li2Mg8Si2 cuboctahedra, faces with two equivalent Li(1)Mg10Si2 cuboctahedra, faces with two equivalent Mg(4)Mg10Si2 cuboctahedra, faces with two equivalent Si(1)Li2Mg10 cuboctahedra, faces with four equivalent Mg(1)Li2Mg8Si2 cuboctahedra, faces with four equivalent Mg(3)Li2Mg8Si2 cuboctahedra, and faces with six equivalent Mg(2)Li2Mg10 cuboctahedra.
LiMg6Si is beta Cu3Ti-derived structured and crystallizes in the orthorhombic Amm2 space group. Li(1) is bonded to two equivalent Mg(2), four equivalent Mg(1), four equivalent Mg(3), and two equivalent Si(1) atoms to form LiMg10Si2 cuboctahedra that share corners with four equivalent Mg(2)Li2Mg10 cuboctahedra, corners with six equivalent Li(1)Mg10Si2 cuboctahedra, corners with eight equivalent Mg(1)Li2Mg8Si2 cuboctahedra, edges with two equivalent Mg(2)Li2Mg10 cuboctahedra, edges with four equivalent Mg(1)Li2Mg8Si2 cuboctahedra, edges with four equivalent Si(1)Li2Mg10 cuboctahedra, edges with eight equivalent Mg(3)Li2Mg8Si2 cuboctahedra, faces with two equivalent Li(1)Mg10Si2 cuboctahedra, faces with two equivalent Mg(2)Li2Mg10 cuboctahedra, faces with two equivalent Si(1)Li2Mg10 cuboctahedra, faces with four equivalent Mg(1)Li2Mg8Si2 cuboctahedra, faces with four equivalent Mg(3)Li2Mg8Si2 cuboctahedra, and faces with six equivalent Mg(4)Mg10Si2 cuboctahedra. Both Li(1)-Mg(2) bond lengths are 3.11 Å. There are two shorter (3.04 Å) and two longer (3.17 Å) Li(1)-Mg(1) bond lengths. All Li(1)-Mg(3) bond lengths are 3.06 Å. Both Li(1)-Si(1) bond lengths are 3.04 Å. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent Li(1), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), and two equivalent Si(1) atoms to form distorted MgLi2Mg8Si2 cuboctahedra that share corners with four equivalent Li(1)Mg10Si2 cuboctahedra, corners with four equivalent Mg(2)Li2Mg10 cuboctahedra, corners with ten equivalent Mg(1)Li2Mg8Si2 cuboctahedra, edges with two equivalent Li(1)Mg10Si2 cuboctahedra, edges with two equivalent Mg(2)Li2Mg10 cuboctahedra, edges with two equivalent Mg(1)Li2Mg8Si2 cuboctahedra, edges with four equivalent Mg(3)Li2Mg8Si2 cuboctahedra, edges with four equivalent Mg(4)Mg10Si2 cuboctahedra, edges with four equivalent Si(1)Li2Mg10 cuboctahedra, faces with two equivalent Li(1)Mg10Si2 cuboctahedra, faces with two equivalent Mg(2)Li2Mg10 cuboctahedra, faces with two equivalent Mg(4)Mg10Si2 cuboctahedra, faces with two equivalent Si(1)Li2Mg10 cuboctahedra, faces with four equivalent Mg(1)Li2Mg8Si2 cuboctahedra, and faces with eight equivalent Mg(3)Li2Mg8Si2 cuboctahedra. There is one shorter (3.03 Å) and one longer (3.18 Å) Mg(1)-Mg(1) bond length. There is one shorter (3.10 Å) and one longer (3.11 Å) Mg(1)-Mg(2) bond length. Both Mg(1)-Mg(3) bond lengths are 3.09 Å. Both Mg(1)-Mg(4) bond lengths are 3.08 Å. Both Mg(1)-Si(1) bond lengths are 3.04 Å. In the second Mg site, Mg(2) is bonded to two equivalent Li(1), two equivalent Mg(4), four equivalent Mg(1), and four equivalent Mg(3) atoms to form MgLi2Mg10 cuboctahedra that share corners with four equivalent Li(1)Mg10Si2 cuboctahedra, corners with six equivalent Mg(2)Li2Mg10 cuboctahedra, corners with eight equivalent Mg(1)Li2Mg8Si2 cuboctahedra, edges with two equivalent Li(1)Mg10Si2 cuboctahedra, edges with four equivalent Mg(1)Li2Mg8Si2 cuboctahedra, edges with four equivalent Mg(4)Mg10Si2 cuboctahedra, edges with eight equivalent Mg(3)Li2Mg8Si2 cuboctahedra, faces with two equivalent Li(1)Mg10Si2 cuboctahedra, faces with two equivalent Mg(2)Li2Mg10 cuboctahedra, faces with two equivalent Mg(4)Mg10Si2 cuboctahedra, faces with four equivalent Mg(1)Li2Mg8Si2 cuboctahedra, faces with four equivalent Mg(3)Li2Mg8Si2 cuboctahedra, and faces with six equivalent Si(1)Li2Mg10 cuboctahedra. Both Mg(2)-Mg(4) bond lengths are 3.06 Å. All Mg(2)-Mg(3) bond lengths are 3.06 Å. In the third Mg site, Mg(3) is bonded to two equivalent Li(1), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), and two equivalent Si(1) atoms to form distorted MgLi2Mg8Si2 cuboctahedra that share corners with four equivalent Mg(4)Mg10Si2 cuboctahedra, corners with four equivalent Si(1)Li2Mg10 cuboctahedra, corners with ten equivalent Mg(3)Li2Mg8Si2 cuboctahedra, edges with two equivalent Mg(3)Li2Mg8Si2 cuboctahedra, edges with two equivalent Mg(4)Mg10Si2 cuboctahedra, edges with two equivalent Si(1)Li2Mg10 cuboctahedra, edges with four equivalent Li(1)Mg10Si2 cuboctahedra, edges with four equivalent Mg(2)Li2Mg10 cuboctahedra, edges with four equivalent Mg(1)Li2Mg8Si2 cuboctahedra, faces with two equivalent Li(1)Mg10Si2 cuboctahedra, faces with two equivalent Mg(2)Li2Mg10 cuboctahedra, faces with two equivalent Mg(4)Mg10Si2 cuboctahedra, faces with two equivalent Si(1)Li2Mg10 cuboctahedra, faces with four equivalent Mg(3)Li2Mg8Si2 cuboctahedra, and faces with eight equivalent Mg(1)Li2Mg8Si2 cuboctahedra. There is one shorter (3.08 Å) and one longer (3.14 Å) Mg(3)-Mg(3) bond length. There is one shorter (3.09 Å) and one longer (3.13 Å) Mg(3)-Mg(4) bond length. There is one shorter (3.07 Å) and one longer (3.14 Å) Mg(3)-Si(1) bond length. In the fourth Mg site, Mg(4) is bonded to two equivalent Mg(2), four equivalent Mg(1), four equivalent Mg(3), and two equivalent Si(1) atoms to form distorted MgMg10Si2 cuboctahedra that share corners with four equivalent Si(1)Li2Mg10 cuboctahedra, corners with six equivalent Mg(4)Mg10Si2 cuboctahedra, corners with eight equivalent Mg(3)Li2Mg8Si2 cuboctahedra, edges with two equivalent Si(1)Li2Mg10 cuboctahedra, edges with four equivalent Mg(2)Li2Mg10 cuboctahedra, edges with four equivalent Mg(3)Li2Mg8Si2 cuboctahedra, edges with eight equivalent Mg(1)Li2Mg8Si2 cuboctahedra, faces with two equivalent Mg(2)Li2Mg10 cuboctahedra, faces with two equivalent Mg(4)Mg10Si2 cuboctahedra, faces with two equivalent Si(1)Li2Mg10 cuboctahedra, faces with four equivalent Mg(1)Li2Mg8Si2 cuboctahedra, faces with four equivalent Mg(3)Li2Mg8Si2 cuboctahedra, and faces with six equivalent Li(1)Mg10Si2 cuboctahedra. Both Mg(4)-Si(1) bond lengths are 3.11 Å. Si(1) is bonded to two equivalent Li(1), two equivalent Mg(4), four equivalent Mg(1), and four equivalent Mg(3) atoms to form SiLi2Mg10 cuboctahedra that share corners with four equivalent Mg(4)Mg10Si2 cuboctahedra, corners with six equivalent Si(1)Li2Mg10 cuboctahedra, corners with eight equivalent Mg(3)Li2Mg8Si2 cuboctahedra, edges with two equivalent Mg(4)Mg10Si2 cuboctahedra, edges with four equivalent Li(1)Mg10Si2 cuboctahedra, edges with four equivalent Mg(3)Li2Mg8Si2 cuboctahedra, edges with eight equivalent Mg(1)Li2Mg8Si2 cuboctahedra, faces with two equivalent Li(1)Mg10Si2 cuboctahedra, faces with two equivalent Mg(4)Mg10Si2 cuboctahedra, faces with two equivalent Si(1)Li2Mg10 cuboctahedra, faces with four equivalent Mg(1)Li2Mg8Si2 cuboctahedra, faces with four equivalent Mg(3)Li2Mg8Si2 cuboctahedra, and faces with six equivalent Mg(2)Li2Mg10 cuboctahedra.