Mg3Tc is Uranium Silicide-like structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a distorted square co-planar geometry to eight equivalent Mg(2) and four equivalent Tc(1) atoms. In the second Mg site, Mg(2) is bonded to four equivalent Mg(1), four equivalent Mg(2), and four equivalent Tc(1) atoms to form distorted MgMg8Tc4 cuboctahedra that share corners with twelve equivalent Mg(2)Mg8Tc4 cuboctahedra, edges with eight equivalent Mg(2)Mg8Tc4 cuboctahedra, edges with eight equivalent Tc(1)Mg12 cuboctahedra, faces with four equivalent Tc(1)Mg12 cuboctahedra, and faces with ten equivalent Mg(2)Mg8Tc4 cuboctahedra. Tc(1) is bonded to four equivalent Mg(1) and eight equivalent Mg(2) atoms to form TcMg12 cuboctahedra that share corners with four equivalent Tc(1)Mg12 cuboctahedra, edges with eight equivalent Tc(1)Mg12 cuboctahedra, edges with sixteen equivalent Mg(2)Mg8Tc4 cuboctahedra, faces with four equivalent Tc(1)Mg12 cuboctahedra, and faces with eight equivalent Mg(2)Mg8Tc4 cuboctahedra.
Mg3Tc is Uranium Silicide-like structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a distorted square co-planar geometry to eight equivalent Mg(2) and four equivalent Tc(1) atoms. All Mg(1)-Mg(2) bond lengths are 2.95 Å. All Mg(1)-Tc(1) bond lengths are 2.89 Å. In the second Mg site, Mg(2) is bonded to four equivalent Mg(1), four equivalent Mg(2), and four equivalent Tc(1) atoms to form distorted MgMg8Tc4 cuboctahedra that share corners with twelve equivalent Mg(2)Mg8Tc4 cuboctahedra, edges with eight equivalent Mg(2)Mg8Tc4 cuboctahedra, edges with eight equivalent Tc(1)Mg12 cuboctahedra, faces with four equivalent Tc(1)Mg12 cuboctahedra, and faces with ten equivalent Mg(2)Mg8Tc4 cuboctahedra. All Mg(2)-Mg(2) bond lengths are 2.89 Å. All Mg(2)-Tc(1) bond lengths are 2.95 Å. Tc(1) is bonded to four equivalent Mg(1) and eight equivalent Mg(2) atoms to form TcMg12 cuboctahedra that share corners with four equivalent Tc(1)Mg12 cuboctahedra, edges with eight equivalent Tc(1)Mg12 cuboctahedra, edges with sixteen equivalent Mg(2)Mg8Tc4 cuboctahedra, faces with four equivalent Tc(1)Mg12 cuboctahedra, and faces with eight equivalent Mg(2)Mg8Tc4 cuboctahedra.