Mg5As crystallizes in the orthorhombic Amm2 space group. There are five inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 12-coordinate geometry to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), and four equivalent As(1) atoms. In the second Mg site, Mg(2) is bonded in a 2-coordinate geometry to two equivalent Mg(1), two equivalent Mg(3), and two equivalent As(1) atoms. In the third Mg site, Mg(3) is bonded to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(5), and four equivalent Mg(4) atoms to form a mixture of face and corner-sharing MgMg12 cuboctahedra. In the fourth Mg site, Mg(4) is bonded in a 2-coordinate geometry to two equivalent Mg(1), four equivalent Mg(3), and two equivalent As(1) atoms. In the fifth Mg site, Mg(5) is bonded in a 2-coordinate geometry to two equivalent Mg(3) and two equivalent As(1) atoms. As(1) is bonded in a 10-coordinate geometry to two equivalent Mg(2), two equivalent Mg(4), two equivalent Mg(5), and four equivalent Mg(1) atoms.
Mg5As crystallizes in the orthorhombic Amm2 space group. There are five inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 12-coordinate geometry to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), and four equivalent As(1) atoms. Both Mg(1)-Mg(1) bond lengths are 3.31 Å. Both Mg(1)-Mg(2) bond lengths are 2.98 Å. Both Mg(1)-Mg(3) bond lengths are 3.12 Å. Both Mg(1)-Mg(4) bond lengths are 3.10 Å. All Mg(1)-As(1) bond lengths are 3.16 Å. In the second Mg site, Mg(2) is bonded in a 2-coordinate geometry to two equivalent Mg(1), two equivalent Mg(3), and two equivalent As(1) atoms. Both Mg(2)-Mg(3) bond lengths are 3.07 Å. Both Mg(2)-As(1) bond lengths are 3.06 Å. In the third Mg site, Mg(3) is bonded to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(5), and four equivalent Mg(4) atoms to form a mixture of face and corner-sharing MgMg12 cuboctahedra. Both Mg(3)-Mg(3) bond lengths are 3.31 Å. Both Mg(3)-Mg(5) bond lengths are 3.16 Å. All Mg(3)-Mg(4) bond lengths are 3.19 Å. In the fourth Mg site, Mg(4) is bonded in a 2-coordinate geometry to two equivalent Mg(1), four equivalent Mg(3), and two equivalent As(1) atoms. Both Mg(4)-As(1) bond lengths are 3.04 Å. In the fifth Mg site, Mg(5) is bonded in a 2-coordinate geometry to two equivalent Mg(3) and two equivalent As(1) atoms. Both Mg(5)-As(1) bond lengths are 2.91 Å. As(1) is bonded in a 10-coordinate geometry to two equivalent Mg(2), two equivalent Mg(4), two equivalent Mg(5), and four equivalent Mg(1) atoms.