Ce5Mg41 crystallizes in the tetragonal I4/m space group. There are eight inequivalent Mg sites. In the first Mg site, Mg(8) is bonded to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(4), two equivalent Mg(5), two equivalent Mg(6), and two equivalent Ce(1) atoms to form a mixture of face and corner-sharing MgCe2Mg10 cuboctahedra. In the second Mg site, Mg(1) is bonded in a 10-coordinate geometry to one Mg(6), one Mg(7), two equivalent Mg(2), two equivalent Mg(4), two equivalent Mg(8), four equivalent Mg(5), one Ce(1), and one Ce(2) atom. In the third Mg site, Mg(2) is bonded in a 12-coordinate geometry to one Mg(1), one Mg(4), one Mg(6), one Mg(8), two equivalent Mg(2), two equivalent Mg(5), two equivalent Mg(7), and two equivalent Ce(1) atoms. In the fourth Mg site, Mg(3) is bonded in a body-centered cubic geometry to eight equivalent Mg(4) atoms. In the fifth Mg site, Mg(4) is bonded in a 12-coordinate geometry to one Mg(1), one Mg(2), one Mg(3), one Mg(6), one Mg(8), two equivalent Mg(4), two equivalent Mg(5), one Ce(2), and two equivalent Ce(1) atoms. In the sixth Mg site, Mg(5) is bonded in a distorted q6 geometry to one Mg(5), one Mg(6), one Mg(7), one Mg(8), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(4), one Ce(1), and one Ce(2) atom. In the seventh Mg site, Mg(6) is bonded to one Mg(1), one Mg(7), two equivalent Mg(2), two equivalent Mg(4), two equivalent Mg(5), two equivalent Mg(8), and two equivalent Ce(1) atoms to form a mixture of distorted face and corner-sharing MgCe2Mg10 cuboctahedra. In the eighth Mg site, Mg(7) is bonded in a 10-coordinate geometry to one Mg(1), one Mg(6), one Mg(7), two equivalent Mg(5), four equivalent Mg(2), and one Ce(1) atom. There are two inequivalent Ce sites. In the first Ce site, Ce(1) is bonded in a 16-coordinate geometry to one Mg(1), one Mg(7), two equivalent Mg(5), two equivalent Mg(6), two equivalent Mg(8), four equivalent Mg(2), and four equivalent Mg(4) atoms. In the second Ce site, Ce(2) is bonded in a 20-coordinate geometry to four equivalent Mg(1), eight equivalent Mg(4), and eight equivalent Mg(5) atoms.
Ce5Mg41 crystallizes in the tetragonal I4/m space group. There are eight inequivalent Mg sites. In the first Mg site, Mg(8) is bonded to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(4), two equivalent Mg(5), two equivalent Mg(6), and two equivalent Ce(1) atoms to form a mixture of face and corner-sharing MgCe2Mg10 cuboctahedra. Both Mg(8)-Mg(1) bond lengths are 3.25 Å. Both Mg(8)-Mg(2) bond lengths are 3.11 Å. Both Mg(8)-Mg(4) bond lengths are 3.14 Å. Both Mg(8)-Mg(5) bond lengths are 3.02 Å. Both Mg(8)-Mg(6) bond lengths are 2.98 Å. Both Mg(8)-Ce(1) bond lengths are 3.72 Å. In the second Mg site, Mg(1) is bonded in a 10-coordinate geometry to one Mg(6), one Mg(7), two equivalent Mg(2), two equivalent Mg(4), two equivalent Mg(8), four equivalent Mg(5), one Ce(1), and one Ce(2) atom. The Mg(1)-Mg(6) bond length is 3.25 Å. The Mg(1)-Mg(7) bond length is 3.33 Å. Both Mg(1)-Mg(2) bond lengths are 3.52 Å. Both Mg(1)-Mg(4) bond lengths are 3.54 Å. There are two shorter (3.11 Å) and two longer (3.23 Å) Mg(1)-Mg(5) bond lengths. The Mg(1)-Ce(1) bond length is 3.51 Å. The Mg(1)-Ce(2) bond length is 3.75 Å. In the third Mg site, Mg(2) is bonded in a 12-coordinate geometry to one Mg(1), one Mg(4), one Mg(6), one Mg(8), two equivalent Mg(2), two equivalent Mg(5), two equivalent Mg(7), and two equivalent Ce(1) atoms. The Mg(2)-Mg(4) bond length is 3.48 Å. The Mg(2)-Mg(6) bond length is 3.07 Å. Both Mg(2)-Mg(2) bond lengths are 3.21 Å. There is one shorter (3.13 Å) and one longer (3.26 Å) Mg(2)-Mg(5) bond length. There is one shorter (3.02 Å) and one longer (3.13 Å) Mg(2)-Mg(7) bond length. There is one shorter (3.68 Å) and one longer (3.71 Å) Mg(2)-Ce(1) bond length. In the fourth Mg site, Mg(3) is bonded in a body-centered cubic geometry to eight equivalent Mg(4) atoms. All Mg(3)-Mg(4) bond lengths are 3.05 Å. In the fifth Mg site, Mg(4) is bonded in a 12-coordinate geometry to one Mg(1), one Mg(2), one Mg(3), one Mg(6), one Mg(8), two equivalent Mg(4), two equivalent Mg(5), one Ce(2), and two equivalent Ce(1) atoms. The Mg(4)-Mg(6) bond length is 3.19 Å. Both Mg(4)-Mg(4) bond lengths are 3.27 Å. There is one shorter (2.98 Å) and one longer (3.02 Å) Mg(4)-Mg(5) bond length. The Mg(4)-Ce(2) bond length is 3.98 Å. There is one shorter (3.51 Å) and one longer (3.53 Å) Mg(4)-Ce(1) bond length. In the sixth Mg site, Mg(5) is bonded in a distorted q6 geometry to one Mg(5), one Mg(6), one Mg(7), one Mg(8), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(4), one Ce(1), and one Ce(2) atom. The Mg(5)-Mg(5) bond length is 3.06 Å. The Mg(5)-Mg(6) bond length is 3.25 Å. The Mg(5)-Mg(7) bond length is 3.12 Å. The Mg(5)-Ce(1) bond length is 3.73 Å. The Mg(5)-Ce(2) bond length is 3.81 Å. In the seventh Mg site, Mg(6) is bonded to one Mg(1), one Mg(7), two equivalent Mg(2), two equivalent Mg(4), two equivalent Mg(5), two equivalent Mg(8), and two equivalent Ce(1) atoms to form a mixture of distorted face and corner-sharing MgCe2Mg10 cuboctahedra. The Mg(6)-Mg(7) bond length is 3.21 Å. There is one shorter (3.43 Å) and one longer (3.50 Å) Mg(6)-Ce(1) bond length. In the eighth Mg site, Mg(7) is bonded in a 10-coordinate geometry to one Mg(1), one Mg(6), one Mg(7), two equivalent Mg(5), four equivalent Mg(2), and one Ce(1) atom. The Mg(7)-Mg(7) bond length is 2.88 Å. The Mg(7)-Ce(1) bond length is 3.68 Å. There are two inequivalent Ce sites. In the first Ce site, Ce(1) is bonded in a 16-coordinate geometry to one Mg(1), one Mg(7), two equivalent Mg(5), two equivalent Mg(6), two equivalent Mg(8), four equivalent Mg(2), and four equivalent Mg(4) atoms. In the second Ce site, Ce(2) is bonded in a 20-coordinate geometry to four equivalent Mg(1), eight equivalent Mg(4), and eight equivalent Mg(5) atoms.