Mg3Ti crystallizes in the orthorhombic Pmm2 space group. There are three inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent Mg(1), two equivalent Mg(2), four equivalent Mg(3), and four equivalent Ti(1) atoms to form MgMg8Ti4 cuboctahedra that share corners with eight equivalent Ti(1)Mg10Ti2 cuboctahedra, corners with ten equivalent Mg(1)Mg8Ti4 cuboctahedra, edges with two equivalent Mg(1)Mg8Ti4 cuboctahedra, edges with four equivalent Mg(2)Mg8Ti4 cuboctahedra, edges with four equivalent Ti(1)Mg10Ti2 cuboctahedra, edges with eight equivalent Mg(3)Mg10Ti2 cuboctahedra, faces with four equivalent Mg(3)Mg10Ti2 cuboctahedra, faces with four equivalent Mg(1)Mg8Ti4 cuboctahedra, faces with four equivalent Ti(1)Mg10Ti2 cuboctahedra, and faces with eight equivalent Mg(2)Mg8Ti4 cuboctahedra. In the second Mg site, Mg(2) is bonded to two equivalent Mg(1), two equivalent Mg(2), four equivalent Mg(3), and four equivalent Ti(1) atoms to form distorted MgMg8Ti4 cuboctahedra that share corners with eight equivalent Mg(3)Mg10Ti2 cuboctahedra, corners with ten equivalent Mg(2)Mg8Ti4 cuboctahedra, edges with two equivalent Mg(2)Mg8Ti4 cuboctahedra, edges with four equivalent Mg(3)Mg10Ti2 cuboctahedra, edges with four equivalent Mg(1)Mg8Ti4 cuboctahedra, edges with eight equivalent Ti(1)Mg10Ti2 cuboctahedra, faces with four equivalent Mg(3)Mg10Ti2 cuboctahedra, faces with four equivalent Mg(2)Mg8Ti4 cuboctahedra, faces with four equivalent Ti(1)Mg10Ti2 cuboctahedra, and faces with eight equivalent Mg(1)Mg8Ti4 cuboctahedra. In the third Mg site, Mg(3) is bonded to two equivalent Mg(3), four equivalent Mg(1), four equivalent Mg(2), and two equivalent Ti(1) atoms to form distorted MgMg10Ti2 cuboctahedra that share corners with eight equivalent Mg(2)Mg8Ti4 cuboctahedra, corners with ten equivalent Mg(3)Mg10Ti2 cuboctahedra, edges with two equivalent Mg(3)Mg10Ti2 cuboctahedra, edges with four equivalent Mg(2)Mg8Ti4 cuboctahedra, edges with four equivalent Ti(1)Mg10Ti2 cuboctahedra, edges with eight equivalent Mg(1)Mg8Ti4 cuboctahedra, faces with four equivalent Mg(3)Mg10Ti2 cuboctahedra, faces with four equivalent Mg(1)Mg8Ti4 cuboctahedra, faces with four equivalent Mg(2)Mg8Ti4 cuboctahedra, and faces with eight equivalent Ti(1)Mg10Ti2 cuboctahedra. Ti(1) is bonded to two equivalent Mg(3), four equivalent Mg(1), four equivalent Mg(2), and two equivalent Ti(1) atoms to form TiMg10Ti2 cuboctahedra that share corners with eight equivalent Mg(1)Mg8Ti4 cuboctahedra, corners with ten equivalent Ti(1)Mg10Ti2 cuboctahedra, edges with two equivalent Ti(1)Mg10Ti2 cuboctahedra, edges with four equivalent Mg(3)Mg10Ti2 cuboctahedra, edges with four equivalent Mg(1)Mg8Ti4 cuboctahedra, edges with eight equivalent Mg(2)Mg8Ti4 cuboctahedra, faces with four equivalent Mg(1)Mg8Ti4 cuboctahedra, faces with four equivalent Mg(2)Mg8Ti4 cuboctahedra, faces with four equivalent Ti(1)Mg10Ti2 cuboctahedra, and faces with eight equivalent Mg(3)Mg10Ti2 cuboctahedra.
Mg3Ti crystallizes in the orthorhombic Pmm2 space group. There are three inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent Mg(1), two equivalent Mg(2), four equivalent Mg(3), and four equivalent Ti(1) atoms to form MgMg8Ti4 cuboctahedra that share corners with eight equivalent Ti(1)Mg10Ti2 cuboctahedra, corners with ten equivalent Mg(1)Mg8Ti4 cuboctahedra, edges with two equivalent Mg(1)Mg8Ti4 cuboctahedra, edges with four equivalent Mg(2)Mg8Ti4 cuboctahedra, edges with four equivalent Ti(1)Mg10Ti2 cuboctahedra, edges with eight equivalent Mg(3)Mg10Ti2 cuboctahedra, faces with four equivalent Mg(3)Mg10Ti2 cuboctahedra, faces with four equivalent Mg(1)Mg8Ti4 cuboctahedra, faces with four equivalent Ti(1)Mg10Ti2 cuboctahedra, and faces with eight equivalent Mg(2)Mg8Ti4 cuboctahedra. Both Mg(1)-Mg(1) bond lengths are 3.07 Å. Both Mg(1)-Mg(2) bond lengths are 3.14 Å. All Mg(1)-Mg(3) bond lengths are 3.12 Å. There are two shorter (3.12 Å) and two longer (3.15 Å) Mg(1)-Ti(1) bond lengths. In the second Mg site, Mg(2) is bonded to two equivalent Mg(1), two equivalent Mg(2), four equivalent Mg(3), and four equivalent Ti(1) atoms to form distorted MgMg8Ti4 cuboctahedra that share corners with eight equivalent Mg(3)Mg10Ti2 cuboctahedra, corners with ten equivalent Mg(2)Mg8Ti4 cuboctahedra, edges with two equivalent Mg(2)Mg8Ti4 cuboctahedra, edges with four equivalent Mg(3)Mg10Ti2 cuboctahedra, edges with four equivalent Mg(1)Mg8Ti4 cuboctahedra, edges with eight equivalent Ti(1)Mg10Ti2 cuboctahedra, faces with four equivalent Mg(3)Mg10Ti2 cuboctahedra, faces with four equivalent Mg(2)Mg8Ti4 cuboctahedra, faces with four equivalent Ti(1)Mg10Ti2 cuboctahedra, and faces with eight equivalent Mg(1)Mg8Ti4 cuboctahedra. Both Mg(2)-Mg(2) bond lengths are 3.07 Å. There are two shorter (3.03 Å) and two longer (3.25 Å) Mg(2)-Mg(3) bond lengths. All Mg(2)-Ti(1) bond lengths are 3.07 Å. In the third Mg site, Mg(3) is bonded to two equivalent Mg(3), four equivalent Mg(1), four equivalent Mg(2), and two equivalent Ti(1) atoms to form distorted MgMg10Ti2 cuboctahedra that share corners with eight equivalent Mg(2)Mg8Ti4 cuboctahedra, corners with ten equivalent Mg(3)Mg10Ti2 cuboctahedra, edges with two equivalent Mg(3)Mg10Ti2 cuboctahedra, edges with four equivalent Mg(2)Mg8Ti4 cuboctahedra, edges with four equivalent Ti(1)Mg10Ti2 cuboctahedra, edges with eight equivalent Mg(1)Mg8Ti4 cuboctahedra, faces with four equivalent Mg(3)Mg10Ti2 cuboctahedra, faces with four equivalent Mg(1)Mg8Ti4 cuboctahedra, faces with four equivalent Mg(2)Mg8Ti4 cuboctahedra, and faces with eight equivalent Ti(1)Mg10Ti2 cuboctahedra. Both Mg(3)-Mg(3) bond lengths are 3.07 Å. Both Mg(3)-Ti(1) bond lengths are 3.08 Å. Ti(1) is bonded to two equivalent Mg(3), four equivalent Mg(1), four equivalent Mg(2), and two equivalent Ti(1) atoms to form TiMg10Ti2 cuboctahedra that share corners with eight equivalent Mg(1)Mg8Ti4 cuboctahedra, corners with ten equivalent Ti(1)Mg10Ti2 cuboctahedra, edges with two equivalent Ti(1)Mg10Ti2 cuboctahedra, edges with four equivalent Mg(3)Mg10Ti2 cuboctahedra, edges with four equivalent Mg(1)Mg8Ti4 cuboctahedra, edges with eight equivalent Mg(2)Mg8Ti4 cuboctahedra, faces with four equivalent Mg(1)Mg8Ti4 cuboctahedra, faces with four equivalent Mg(2)Mg8Ti4 cuboctahedra, faces with four equivalent Ti(1)Mg10Ti2 cuboctahedra, and faces with eight equivalent Mg(3)Mg10Ti2 cuboctahedra. Both Ti(1)-Ti(1) bond lengths are 3.07 Å.