Mg6LaC crystallizes in the orthorhombic Amm2 space group. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 5-coordinate geometry to two equivalent Mg(2), two equivalent Mg(3), and two equivalent Mg(4) atoms. In the second Mg site, Mg(2) is bonded to two equivalent Mg(4), four equivalent Mg(1), four equivalent Mg(3), and two equivalent La(1) atoms to form a mixture of distorted corner and face-sharing MgLa2Mg10 cuboctahedra. In the third Mg site, Mg(3) is bonded in a 9-coordinate geometry to one Mg(3), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(4), and two equivalent La(1) atoms. In the fourth Mg site, Mg(4) is bonded in a 10-coordinate geometry to two equivalent Mg(2), four equivalent Mg(1), and four equivalent Mg(3) atoms. La(1) is bonded in a bent 120 degrees geometry to two equivalent Mg(2), four equivalent Mg(3), and two equivalent C(1) atoms. C(1) is bonded in a bent 120 degrees geometry to two equivalent La(1) atoms.
Mg6LaC crystallizes in the orthorhombic Amm2 space group. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 5-coordinate geometry to two equivalent Mg(2), two equivalent Mg(3), and two equivalent Mg(4) atoms. There is one shorter (3.28 Å) and one longer (3.48 Å) Mg(1)-Mg(2) bond length. Both Mg(1)-Mg(3) bond lengths are 2.90 Å. Both Mg(1)-Mg(4) bond lengths are 3.08 Å. In the second Mg site, Mg(2) is bonded to two equivalent Mg(4), four equivalent Mg(1), four equivalent Mg(3), and two equivalent La(1) atoms to form a mixture of distorted corner and face-sharing MgLa2Mg10 cuboctahedra. Both Mg(2)-Mg(4) bond lengths are 3.01 Å. All Mg(2)-Mg(3) bond lengths are 2.96 Å. Both Mg(2)-La(1) bond lengths are 3.42 Å. In the third Mg site, Mg(3) is bonded in a 9-coordinate geometry to one Mg(3), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(4), and two equivalent La(1) atoms. The Mg(3)-Mg(3) bond length is 3.11 Å. There is one shorter (3.38 Å) and one longer (3.39 Å) Mg(3)-Mg(4) bond length. Both Mg(3)-La(1) bond lengths are 3.27 Å. In the fourth Mg site, Mg(4) is bonded in a 10-coordinate geometry to two equivalent Mg(2), four equivalent Mg(1), and four equivalent Mg(3) atoms. La(1) is bonded in a bent 120 degrees geometry to two equivalent Mg(2), four equivalent Mg(3), and two equivalent C(1) atoms. Both La(1)-C(1) bond lengths are 2.65 Å. C(1) is bonded in a bent 120 degrees geometry to two equivalent La(1) atoms.