ThMg2 is Hexagonal Laves structured and crystallizes in the hexagonal P6_3/mmc space group. There are three inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent Mg(3); four equivalent Mg(1); two equivalent Th(1); and four Th(2,2) atoms to form a mixture of face, corner, and edge-sharing MgTh6Mg6 cuboctahedra. In the second Mg site, Mg(2) is bonded to two equivalent Mg(3); four equivalent Mg(2); two equivalent Th(2); and four Th(1,1) atoms to form a mixture of face, corner, and edge-sharing MgTh6Mg6 cuboctahedra. In the third Mg site, Mg(3) is bonded to three equivalent Mg(1), three equivalent Mg(2), three equivalent Th(1), and three equivalent Th(2) atoms to form a mixture of face, corner, and edge-sharing MgTh6Mg6 cuboctahedra. There are four inequivalent Th sites. In the first Th site, Th(1) is bonded in a 16-coordinate geometry to three equivalent Mg(1), three equivalent Mg(3), six equivalent Mg(2), one Th(1), and three equivalent Th(2) atoms. In the second Th site, Th(2) is bonded in a 16-coordinate geometry to three equivalent Mg(2), three equivalent Mg(3), six equivalent Mg(1), one Th(2), and three equivalent Th(1) atoms. In the third Th site, Th(1) is bonded in a 16-coordinate geometry to three equivalent Mg(1), three equivalent Mg(3), six equivalent Mg(2), one Th(1), and three equivalent Th(2) atoms. In the fourth Th site, Th(2) is bonded in a 16-coordinate geometry to three equivalent Mg(2), three equivalent Mg(3), six equivalent Mg(1), one Th(2), and three equivalent Th(1) atoms.
ThMg2 is Hexagonal Laves structured and crystallizes in the hexagonal P6_3/mmc space group. There are three inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent Mg(3); four equivalent Mg(1); two equivalent Th(1); and four Th(2,2) atoms to form a mixture of face, corner, and edge-sharing MgTh6Mg6 cuboctahedra. Both Mg(1)-Mg(3) bond lengths are 3.02 Å. All Mg(1)-Mg(1) bond lengths are 3.04 Å. Both Mg(1)-Th(1) bond lengths are 3.53 Å. All Mg(1)-Th(2,2) bond lengths are 3.52 Å. In the second Mg site, Mg(2) is bonded to two equivalent Mg(3); four equivalent Mg(2); two equivalent Th(2); and four Th(1,1) atoms to form a mixture of face, corner, and edge-sharing MgTh6Mg6 cuboctahedra. Both Mg(2)-Mg(3) bond lengths are 3.02 Å. There are two shorter (2.94 Å) and two longer (3.15 Å) Mg(2)-Mg(2) bond lengths. Both Mg(2)-Th(2) bond lengths are 3.53 Å. All Mg(2)-Th(1,1) bond lengths are 3.53 Å. In the third Mg site, Mg(3) is bonded to three equivalent Mg(1), three equivalent Mg(2), three equivalent Th(1), and three equivalent Th(2) atoms to form a mixture of face, corner, and edge-sharing MgTh6Mg6 cuboctahedra. All Mg(3)-Th(1) bond lengths are 3.56 Å. All Mg(3)-Th(2) bond lengths are 3.58 Å. There are four inequivalent Th sites. In the first Th site, Th(1) is bonded in a 16-coordinate geometry to three equivalent Mg(1), three equivalent Mg(3), six equivalent Mg(2), one Th(1), and three equivalent Th(2) atoms. All Th(1)-Mg(1) bond lengths are 3.53 Å. The Th(1)-Th(1) bond length is 3.60 Å. All Th(1)-Th(2) bond lengths are 3.74 Å. In the second Th site, Th(2) is bonded in a 16-coordinate geometry to three equivalent Mg(2), three equivalent Mg(3), six equivalent Mg(1), one Th(2), and three equivalent Th(1) atoms. The Th(2)-Th(2) bond length is 3.53 Å. In the third Th site, Th(1) is bonded in a 16-coordinate geometry to three equivalent Mg(1), three equivalent Mg(3), six equivalent Mg(2), one Th(1), and three equivalent Th(2) atoms. All Th(1)-Mg(3) bond lengths are 3.56 Å. All Th(1)-Th(2) bond lengths are 3.74 Å. In the fourth Th site, Th(2) is bonded in a 16-coordinate geometry to three equivalent Mg(2), three equivalent Mg(3), six equivalent Mg(1), one Th(2), and three equivalent Th(1) atoms. All Th(2)-Mg(2) bond lengths are 3.53 Å. All Th(2)-Mg(3) bond lengths are 3.58 Å. The Th(2)-Th(2) bond length is 3.53 Å.