MgLi2 crystallizes in the monoclinic Cm space group. There are four inequivalent Li sites. In the first Li site, Li(1) is bonded to two equivalent Li(1), two equivalent Li(3), two equivalent Li(4), three equivalent Li(2), one Mg(1), and two equivalent Mg(2) atoms to form distorted LiLi9Mg3 cuboctahedra that share corners with six equivalent Li(4)Li7Mg5 cuboctahedra, corners with six equivalent Li(3)Li8Mg4 cuboctahedra, corners with six equivalent Li(1)Li9Mg3 cuboctahedra, edges with two equivalent Li(2)Li8Mg4 cuboctahedra, edges with three equivalent Li(4)Li7Mg5 cuboctahedra, edges with three equivalent Li(3)Li8Mg4 cuboctahedra, edges with four equivalent Mg(1)Li8Mg4 cuboctahedra, edges with six equivalent Mg(2)Li8Mg4 cuboctahedra, faces with two equivalent Li(1)Li9Mg3 cuboctahedra, faces with three equivalent Li(4)Li7Mg5 cuboctahedra, faces with three equivalent Li(3)Li8Mg4 cuboctahedra, faces with three equivalent Mg(2)Li8Mg4 cuboctahedra, faces with four equivalent Mg(1)Li8Mg4 cuboctahedra, and faces with five equivalent Li(2)Li8Mg4 cuboctahedra. In the second Li site, Li(2) is bonded to one Li(4), two equivalent Li(2), two equivalent Li(3), three equivalent Li(1), two equivalent Mg(1), and two equivalent Mg(2) atoms to form distorted LiLi8Mg4 cuboctahedra that share corners with six equivalent Li(2)Li8Mg4 cuboctahedra, corners with six equivalent Mg(1)Li8Mg4 cuboctahedra, corners with six equivalent Mg(2)Li8Mg4 cuboctahedra, edges with two equivalent Li(1)Li9Mg3 cuboctahedra, edges with three equivalent Mg(1)Li8Mg4 cuboctahedra, edges with three equivalent Mg(2)Li8Mg4 cuboctahedra, edges with four equivalent Li(4)Li7Mg5 cuboctahedra, edges with six equivalent Li(3)Li8Mg4 cuboctahedra, faces with two equivalent Li(2)Li8Mg4 cuboctahedra, faces with three equivalent Li(3)Li8Mg4 cuboctahedra, faces with three equivalent Mg(1)Li8Mg4 cuboctahedra, faces with three equivalent Mg(2)Li8Mg4 cuboctahedra, faces with four equivalent Li(4)Li7Mg5 cuboctahedra, and faces with five equivalent Li(1)Li9Mg3 cuboctahedra. In the third Li site, Li(3) is bonded to two equivalent Li(1), two equivalent Li(2), two equivalent Li(3), two equivalent Li(4), one Mg(2), and three equivalent Mg(1) atoms to form distorted LiLi8Mg4 cuboctahedra that share corners with six equivalent Li(4)Li7Mg5 cuboctahedra, corners with six equivalent Li(3)Li8Mg4 cuboctahedra, corners with six equivalent Li(1)Li9Mg3 cuboctahedra, edges with two equivalent Mg(1)Li8Mg4 cuboctahedra, edges with three equivalent Li(4)Li7Mg5 cuboctahedra, edges with three equivalent Li(1)Li9Mg3 cuboctahedra, edges with four equivalent Mg(2)Li8Mg4 cuboctahedra, edges with six equivalent Li(2)Li8Mg4 cuboctahedra, faces with two equivalent Li(3)Li8Mg4 cuboctahedra, faces with three equivalent Li(4)Li7Mg5 cuboctahedra, faces with three equivalent Li(2)Li8Mg4 cuboctahedra, faces with three equivalent Li(1)Li9Mg3 cuboctahedra, faces with four equivalent Mg(2)Li8Mg4 cuboctahedra, and faces with five equivalent Mg(1)Li8Mg4 cuboctahedra. In the fourth Li site, Li(4) is bonded to one Li(2), two equivalent Li(1), two equivalent Li(3), two equivalent Li(4), two equivalent Mg(1), and three equivalent Mg(2) atoms to form distorted LiLi7Mg5 cuboctahedra that share corners with six equivalent Li(4)Li7Mg5 cuboctahedra, corners with six equivalent Li(3)Li8Mg4 cuboctahedra, corners with six equivalent Li(1)Li9Mg3 cuboctahedra, edges with two equivalent Mg(2)Li8Mg4 cuboctahedra, edges with three equivalent Li(3)Li8Mg4 cuboctahedra, edges with three equivalent Li(1)Li9Mg3 cuboctahedra, edges with four equivalent Li(2)Li8Mg4 cuboctahedra, edges with six equivalent Mg(1)Li8Mg4 cuboctahedra, faces with two equivalent Li(4)Li7Mg5 cuboctahedra, faces with three equivalent Li(3)Li8Mg4 cuboctahedra, faces with three equivalent Li(1)Li9Mg3 cuboctahedra, faces with three equivalent Mg(1)Li8Mg4 cuboctahedra, faces with four equivalent Li(2)Li8Mg4 cuboctahedra, and faces with five equivalent Mg(2)Li8Mg4 cuboctahedra. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to one Li(1), two equivalent Li(2), two equivalent Li(4), three equivalent Li(3), two equivalent Mg(1), and two equivalent Mg(2) atoms to form distorted MgLi8Mg4 cuboctahedra that share corners with six equivalent Li(2)Li8Mg4 cuboctahedra, corners with six equivalent Mg(1)Li8Mg4 cuboctahedra, corners with six equivalent Mg(2)Li8Mg4 cuboctahedra, edges with two equivalent Li(3)Li8Mg4 cuboctahedra, edges with three equivalent Li(2)Li8Mg4 cuboctahedra, edges with three equivalent Mg(2)Li8Mg4 cuboctahedra, edges with four equivalent Li(1)Li9Mg3 cuboctahedra, edges with six equivalent Li(4)Li7Mg5 cuboctahedra, faces with two equivalent Mg(1)Li8Mg4 cuboctahedra, faces with three equivalent Li(4)Li7Mg5 cuboctahedra, faces with three equivalent Li(2)Li8Mg4 cuboctahedra, faces with three equivalent Mg(2)Li8Mg4 cuboctahedra, faces with four equivalent Li(1)Li9Mg3 cuboctahedra, and faces with five equivalent Li(3)Li8Mg4 cuboctahedra. In the second Mg site, Mg(2) is bonded to one Li(3), two equivalent Li(1), two equivalent Li(2), three equivalent Li(4), two equivalent Mg(1), and two equivalent Mg(2) atoms to form distorted MgLi8Mg4 cuboctahedra that share corners with six equivalent Li(2)Li8Mg4 cuboctahedra, corners with six equivalent Mg(1)Li8Mg4 cuboctahedra, corners with six equivalent Mg(2)Li8Mg4 cuboctahedra, edges with two equivalent Li(4)Li7Mg5 cuboctahedra, edges with three equivalent Li(2)Li8Mg4 cuboctahedra, edges with three equivalent Mg(1)Li8Mg4 cuboctahedra, edges with four equivalent Li(3)Li8Mg4 cuboctahedra, edges with six equivalent Li(1)Li9Mg3 cuboctahedra, faces with two equivalent Mg(2)Li8Mg4 cuboctahedra, faces with three equivalent Li(2)Li8Mg4 cuboctahedra, faces with three equivalent Li(1)Li9Mg3 cuboctahedra, faces with three equivalent Mg(1)Li8Mg4 cuboctahedra, faces with four equivalent Li(3)Li8Mg4 cuboctahedra, and faces with five equivalent Li(4)Li7Mg5 cuboctahedra.
MgLi2 crystallizes in the monoclinic Cm space group. There are four inequivalent Li sites. In the first Li site, Li(1) is bonded to two equivalent Li(1), two equivalent Li(3), two equivalent Li(4), three equivalent Li(2), one Mg(1), and two equivalent Mg(2) atoms to form distorted LiLi9Mg3 cuboctahedra that share corners with six equivalent Li(4)Li7Mg5 cuboctahedra, corners with six equivalent Li(3)Li8Mg4 cuboctahedra, corners with six equivalent Li(1)Li9Mg3 cuboctahedra, edges with two equivalent Li(2)Li8Mg4 cuboctahedra, edges with three equivalent Li(4)Li7Mg5 cuboctahedra, edges with three equivalent Li(3)Li8Mg4 cuboctahedra, edges with four equivalent Mg(1)Li8Mg4 cuboctahedra, edges with six equivalent Mg(2)Li8Mg4 cuboctahedra, faces with two equivalent Li(1)Li9Mg3 cuboctahedra, faces with three equivalent Li(4)Li7Mg5 cuboctahedra, faces with three equivalent Li(3)Li8Mg4 cuboctahedra, faces with three equivalent Mg(2)Li8Mg4 cuboctahedra, faces with four equivalent Mg(1)Li8Mg4 cuboctahedra, and faces with five equivalent Li(2)Li8Mg4 cuboctahedra. Both Li(1)-Li(1) bond lengths are 3.10 Å. Both Li(1)-Li(3) bond lengths are 3.05 Å. Both Li(1)-Li(4) bond lengths are 3.05 Å. All Li(1)-Li(2) bond lengths are 3.07 Å. The Li(1)-Mg(1) bond length is 3.06 Å. Both Li(1)-Mg(2) bond lengths are 3.07 Å. In the second Li site, Li(2) is bonded to one Li(4), two equivalent Li(2), two equivalent Li(3), three equivalent Li(1), two equivalent Mg(1), and two equivalent Mg(2) atoms to form distorted LiLi8Mg4 cuboctahedra that share corners with six equivalent Li(2)Li8Mg4 cuboctahedra, corners with six equivalent Mg(1)Li8Mg4 cuboctahedra, corners with six equivalent Mg(2)Li8Mg4 cuboctahedra, edges with two equivalent Li(1)Li9Mg3 cuboctahedra, edges with three equivalent Mg(1)Li8Mg4 cuboctahedra, edges with three equivalent Mg(2)Li8Mg4 cuboctahedra, edges with four equivalent Li(4)Li7Mg5 cuboctahedra, edges with six equivalent Li(3)Li8Mg4 cuboctahedra, faces with two equivalent Li(2)Li8Mg4 cuboctahedra, faces with three equivalent Li(3)Li8Mg4 cuboctahedra, faces with three equivalent Mg(1)Li8Mg4 cuboctahedra, faces with three equivalent Mg(2)Li8Mg4 cuboctahedra, faces with four equivalent Li(4)Li7Mg5 cuboctahedra, and faces with five equivalent Li(1)Li9Mg3 cuboctahedra. The Li(2)-Li(4) bond length is 3.08 Å. Both Li(2)-Li(2) bond lengths are 3.10 Å. Both Li(2)-Li(3) bond lengths are 3.08 Å. Both Li(2)-Mg(1) bond lengths are 3.03 Å. Both Li(2)-Mg(2) bond lengths are 3.01 Å. In the third Li site, Li(3) is bonded to two equivalent Li(1), two equivalent Li(2), two equivalent Li(3), two equivalent Li(4), one Mg(2), and three equivalent Mg(1) atoms to form distorted LiLi8Mg4 cuboctahedra that share corners with six equivalent Li(4)Li7Mg5 cuboctahedra, corners with six equivalent Li(3)Li8Mg4 cuboctahedra, corners with six equivalent Li(1)Li9Mg3 cuboctahedra, edges with two equivalent Mg(1)Li8Mg4 cuboctahedra, edges with three equivalent Li(4)Li7Mg5 cuboctahedra, edges with three equivalent Li(1)Li9Mg3 cuboctahedra, edges with four equivalent Mg(2)Li8Mg4 cuboctahedra, edges with six equivalent Li(2)Li8Mg4 cuboctahedra, faces with two equivalent Li(3)Li8Mg4 cuboctahedra, faces with three equivalent Li(4)Li7Mg5 cuboctahedra, faces with three equivalent Li(2)Li8Mg4 cuboctahedra, faces with three equivalent Li(1)Li9Mg3 cuboctahedra, faces with four equivalent Mg(2)Li8Mg4 cuboctahedra, and faces with five equivalent Mg(1)Li8Mg4 cuboctahedra. Both Li(3)-Li(3) bond lengths are 3.10 Å. Both Li(3)-Li(4) bond lengths are 3.06 Å. The Li(3)-Mg(2) bond length is 3.11 Å. There is one shorter (3.05 Å) and two longer (3.08 Å) Li(3)-Mg(1) bond lengths. In the fourth Li site, Li(4) is bonded to one Li(2), two equivalent Li(1), two equivalent Li(3), two equivalent Li(4), two equivalent Mg(1), and three equivalent Mg(2) atoms to form distorted LiLi7Mg5 cuboctahedra that share corners with six equivalent Li(4)Li7Mg5 cuboctahedra, corners with six equivalent Li(3)Li8Mg4 cuboctahedra, corners with six equivalent Li(1)Li9Mg3 cuboctahedra, edges with two equivalent Mg(2)Li8Mg4 cuboctahedra, edges with three equivalent Li(3)Li8Mg4 cuboctahedra, edges with three equivalent Li(1)Li9Mg3 cuboctahedra, edges with four equivalent Li(2)Li8Mg4 cuboctahedra, edges with six equivalent Mg(1)Li8Mg4 cuboctahedra, faces with two equivalent Li(4)Li7Mg5 cuboctahedra, faces with three equivalent Li(3)Li8Mg4 cuboctahedra, faces with three equivalent Li(1)Li9Mg3 cuboctahedra, faces with three equivalent Mg(1)Li8Mg4 cuboctahedra, faces with four equivalent Li(2)Li8Mg4 cuboctahedra, and faces with five equivalent Mg(2)Li8Mg4 cuboctahedra. Both Li(4)-Li(4) bond lengths are 3.10 Å. Both Li(4)-Mg(1) bond lengths are 3.09 Å. There are two shorter (3.06 Å) and one longer (3.10 Å) Li(4)-Mg(2) bond length. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to one Li(1), two equivalent Li(2), two equivalent Li(4), three equivalent Li(3), two equivalent Mg(1), and two equivalent Mg(2) atoms to form distorted MgLi8Mg4 cuboctahedra that share corners with six equivalent Li(2)Li8Mg4 cuboctahedra, corners with six equivalent Mg(1)Li8Mg4 cuboctahedra, corners with six equivalent Mg(2)Li8Mg4 cuboctahedra, edges with two equivalent Li(3)Li8Mg4 cuboctahedra, edges with three equivalent Li(2)Li8Mg4 cuboctahedra, edges with three equivalent Mg(2)Li8Mg4 cuboctahedra, edges with four equivalent Li(1)Li9Mg3 cuboctahedra, edges with six equivalent Li(4)Li7Mg5 cuboctahedra, faces with two equivalent Mg(1)Li8Mg4 cuboctahedra, faces with three equivalent Li(4)Li7Mg5 cuboctahedra, faces with three equivalent Li(2)Li8Mg4 cuboctahedra, faces with three equivalent Mg(2)Li8Mg4 cuboctahedra, faces with four equivalent Li(1)Li9Mg3 cuboctahedra, and faces with five equivalent Li(3)Li8Mg4 cuboctahedra. Both Mg(1)-Mg(1) bond lengths are 3.10 Å. Both Mg(1)-Mg(2) bond lengths are 3.13 Å. In the second Mg site, Mg(2) is bonded to one Li(3), two equivalent Li(1), two equivalent Li(2), three equivalent Li(4), two equivalent Mg(1), and two equivalent Mg(2) atoms to form distorted MgLi8Mg4 cuboctahedra that share corners with six equivalent Li(2)Li8Mg4 cuboctahedra, corners with six equivalent Mg(1)Li8Mg4 cuboctahedra, corners with six equivalent Mg(2)Li8Mg4 cuboctahedra, edges with two equivalent Li(4)Li7Mg5 cuboctahedra, edges with three equivalent Li(2)Li8Mg4 cuboctahedra, edges with three equivalent Mg(1)Li8Mg4 cuboctahedra, edges with four equivalent Li(3)Li8Mg4 cuboctahedra, edges with six equivalent Li(1)Li9Mg3 cuboctahedra, faces with two equivalent Mg(2)Li8Mg4 cuboctahedra, faces with three equivalent Li(2)Li8Mg4 cuboctahedra, faces with three equivalent Li(1)Li9Mg3 cuboctahedra, faces with three equivalent Mg(1)Li8Mg4 cuboctahedra, faces with four equivalent Li(3)Li8Mg4 cuboctahedra, and faces with five equivalent Li(4)Li7Mg5 cuboctahedra. Both Mg(2)-Mg(2) bond lengths are 3.10 Å.