MgNd5 crystallizes in the orthorhombic Amm2 space group. Mg(1) is bonded in a distorted q6 geometry to two equivalent Nd(3), two equivalent Nd(4), two equivalent Nd(5), and four equivalent Nd(2) atoms. There are five inequivalent Nd sites. In the first Nd site, Nd(1) is bonded to two equivalent Nd(1), two equivalent Nd(2), two equivalent Nd(3), two equivalent Nd(5), and four equivalent Nd(4) atoms to form NdNd12 cuboctahedra that share corners with six equivalent Nd(3)Nd10Mg2 cuboctahedra, corners with six equivalent Nd(1)Nd12 cuboctahedra, corners with six equivalent Nd(2)Nd8Mg4 cuboctahedra, edges with three equivalent Nd(3)Nd10Mg2 cuboctahedra, edges with three equivalent Nd(2)Nd8Mg4 cuboctahedra, edges with four equivalent Nd(4)Nd10Mg2 cuboctahedra, faces with two equivalent Nd(3)Nd10Mg2 cuboctahedra, faces with two equivalent Nd(2)Nd8Mg4 cuboctahedra, faces with four equivalent Nd(4)Nd10Mg2 cuboctahedra, faces with four equivalent Nd(1)Nd12 cuboctahedra, and faces with six equivalent Nd(5)Nd10Mg2 cuboctahedra. In the second Nd site, Nd(2) is bonded to four equivalent Mg(1), two equivalent Nd(1), two equivalent Nd(2), two equivalent Nd(3), and two equivalent Nd(4) atoms to form distorted NdNd8Mg4 cuboctahedra that share corners with six equivalent Nd(3)Nd10Mg2 cuboctahedra, corners with six equivalent Nd(1)Nd12 cuboctahedra, corners with six equivalent Nd(2)Nd8Mg4 cuboctahedra, edges with three equivalent Nd(3)Nd10Mg2 cuboctahedra, edges with three equivalent Nd(1)Nd12 cuboctahedra, edges with eight equivalent Nd(5)Nd10Mg2 cuboctahedra, faces with two equivalent Nd(3)Nd10Mg2 cuboctahedra, faces with two equivalent Nd(5)Nd10Mg2 cuboctahedra, faces with two equivalent Nd(1)Nd12 cuboctahedra, faces with four equivalent Nd(2)Nd8Mg4 cuboctahedra, and faces with six equivalent Nd(4)Nd10Mg2 cuboctahedra. In the third Nd site, Nd(3) is bonded to two equivalent Mg(1), two equivalent Nd(1), two equivalent Nd(2), two equivalent Nd(3), and four equivalent Nd(5) atoms to form NdNd10Mg2 cuboctahedra that share corners with six equivalent Nd(3)Nd10Mg2 cuboctahedra, corners with six equivalent Nd(1)Nd12 cuboctahedra, corners with six equivalent Nd(2)Nd8Mg4 cuboctahedra, edges with three equivalent Nd(1)Nd12 cuboctahedra, edges with three equivalent Nd(2)Nd8Mg4 cuboctahedra, edges with four equivalent Nd(5)Nd10Mg2 cuboctahedra, edges with eight equivalent Nd(4)Nd10Mg2 cuboctahedra, faces with two equivalent Nd(4)Nd10Mg2 cuboctahedra, faces with two equivalent Nd(1)Nd12 cuboctahedra, faces with two equivalent Nd(2)Nd8Mg4 cuboctahedra, faces with four equivalent Nd(3)Nd10Mg2 cuboctahedra, and faces with four equivalent Nd(5)Nd10Mg2 cuboctahedra. In the fourth Nd site, Nd(4) is bonded to two equivalent Mg(1), two equivalent Nd(2), two equivalent Nd(4), two equivalent Nd(5), and four equivalent Nd(1) atoms to form NdNd10Mg2 cuboctahedra that share corners with six equivalent Nd(4)Nd10Mg2 cuboctahedra, corners with six equivalent Nd(5)Nd10Mg2 cuboctahedra, edges with three equivalent Nd(5)Nd10Mg2 cuboctahedra, edges with four equivalent Nd(1)Nd12 cuboctahedra, edges with eight equivalent Nd(3)Nd10Mg2 cuboctahedra, faces with two equivalent Nd(3)Nd10Mg2 cuboctahedra, faces with two equivalent Nd(5)Nd10Mg2 cuboctahedra, faces with four equivalent Nd(4)Nd10Mg2 cuboctahedra, faces with four equivalent Nd(1)Nd12 cuboctahedra, and faces with six equivalent Nd(2)Nd8Mg4 cuboctahedra. In the fifth Nd site, Nd(5) is bonded to two equivalent Mg(1), two equivalent Nd(1), two equivalent Nd(4), two equivalent Nd(5), and four equivalent Nd(3) atoms to form distorted NdNd10Mg2 cuboctahedra that share corners with six equivalent Nd(4)Nd10Mg2 cuboctahedra, corners with six equivalent Nd(5)Nd10Mg2 cuboctahedra, edges with three equivalent Nd(4)Nd10Mg2 cuboctahedra, edges with four equivalent Nd(3)Nd10Mg2 cuboctahedra, edges with eight equivalent Nd(2)Nd8Mg4 cuboctahedra, faces with two equivalent Nd(4)Nd10Mg2 cuboctahedra, faces with two equivalent Nd(2)Nd8Mg4 cuboctahedra, faces with four equivalent Nd(3)Nd10Mg2 cuboctahedra, faces with four equivalent Nd(5)Nd10Mg2 cuboctahedra, and faces with six equivalent Nd(1)Nd12 cuboctahedra.
MgNd5 crystallizes in the orthorhombic Amm2 space group. Mg(1) is bonded in a distorted q6 geometry to two equivalent Nd(3), two equivalent Nd(4), two equivalent Nd(5), and four equivalent Nd(2) atoms. Both Mg(1)-Nd(3) bond lengths are 3.60 Å. Both Mg(1)-Nd(4) bond lengths are 3.57 Å. Both Mg(1)-Nd(5) bond lengths are 3.49 Å. All Mg(1)-Nd(2) bond lengths are 3.58 Å. There are five inequivalent Nd sites. In the first Nd site, Nd(1) is bonded to two equivalent Nd(1), two equivalent Nd(2), two equivalent Nd(3), two equivalent Nd(5), and four equivalent Nd(4) atoms to form NdNd12 cuboctahedra that share corners with six equivalent Nd(3)Nd10Mg2 cuboctahedra, corners with six equivalent Nd(1)Nd12 cuboctahedra, corners with six equivalent Nd(2)Nd8Mg4 cuboctahedra, edges with three equivalent Nd(3)Nd10Mg2 cuboctahedra, edges with three equivalent Nd(2)Nd8Mg4 cuboctahedra, edges with four equivalent Nd(4)Nd10Mg2 cuboctahedra, faces with two equivalent Nd(3)Nd10Mg2 cuboctahedra, faces with two equivalent Nd(2)Nd8Mg4 cuboctahedra, faces with four equivalent Nd(4)Nd10Mg2 cuboctahedra, faces with four equivalent Nd(1)Nd12 cuboctahedra, and faces with six equivalent Nd(5)Nd10Mg2 cuboctahedra. Both Nd(1)-Nd(1) bond lengths are 3.70 Å. Both Nd(1)-Nd(2) bond lengths are 3.64 Å. Both Nd(1)-Nd(3) bond lengths are 3.68 Å. Both Nd(1)-Nd(5) bond lengths are 3.73 Å. All Nd(1)-Nd(4) bond lengths are 3.60 Å. In the second Nd site, Nd(2) is bonded to four equivalent Mg(1), two equivalent Nd(1), two equivalent Nd(2), two equivalent Nd(3), and two equivalent Nd(4) atoms to form distorted NdNd8Mg4 cuboctahedra that share corners with six equivalent Nd(3)Nd10Mg2 cuboctahedra, corners with six equivalent Nd(1)Nd12 cuboctahedra, corners with six equivalent Nd(2)Nd8Mg4 cuboctahedra, edges with three equivalent Nd(3)Nd10Mg2 cuboctahedra, edges with three equivalent Nd(1)Nd12 cuboctahedra, edges with eight equivalent Nd(5)Nd10Mg2 cuboctahedra, faces with two equivalent Nd(3)Nd10Mg2 cuboctahedra, faces with two equivalent Nd(5)Nd10Mg2 cuboctahedra, faces with two equivalent Nd(1)Nd12 cuboctahedra, faces with four equivalent Nd(2)Nd8Mg4 cuboctahedra, and faces with six equivalent Nd(4)Nd10Mg2 cuboctahedra. Both Nd(2)-Nd(2) bond lengths are 3.70 Å. Both Nd(2)-Nd(3) bond lengths are 3.48 Å. Both Nd(2)-Nd(4) bond lengths are 3.66 Å. In the third Nd site, Nd(3) is bonded to two equivalent Mg(1), two equivalent Nd(1), two equivalent Nd(2), two equivalent Nd(3), and four equivalent Nd(5) atoms to form NdNd10Mg2 cuboctahedra that share corners with six equivalent Nd(3)Nd10Mg2 cuboctahedra, corners with six equivalent Nd(1)Nd12 cuboctahedra, corners with six equivalent Nd(2)Nd8Mg4 cuboctahedra, edges with three equivalent Nd(1)Nd12 cuboctahedra, edges with three equivalent Nd(2)Nd8Mg4 cuboctahedra, edges with four equivalent Nd(5)Nd10Mg2 cuboctahedra, edges with eight equivalent Nd(4)Nd10Mg2 cuboctahedra, faces with two equivalent Nd(4)Nd10Mg2 cuboctahedra, faces with two equivalent Nd(1)Nd12 cuboctahedra, faces with two equivalent Nd(2)Nd8Mg4 cuboctahedra, faces with four equivalent Nd(3)Nd10Mg2 cuboctahedra, and faces with four equivalent Nd(5)Nd10Mg2 cuboctahedra. Both Nd(3)-Nd(3) bond lengths are 3.70 Å. All Nd(3)-Nd(5) bond lengths are 3.59 Å. In the fourth Nd site, Nd(4) is bonded to two equivalent Mg(1), two equivalent Nd(2), two equivalent Nd(4), two equivalent Nd(5), and four equivalent Nd(1) atoms to form NdNd10Mg2 cuboctahedra that share corners with six equivalent Nd(4)Nd10Mg2 cuboctahedra, corners with six equivalent Nd(5)Nd10Mg2 cuboctahedra, edges with three equivalent Nd(5)Nd10Mg2 cuboctahedra, edges with four equivalent Nd(1)Nd12 cuboctahedra, edges with eight equivalent Nd(3)Nd10Mg2 cuboctahedra, faces with two equivalent Nd(3)Nd10Mg2 cuboctahedra, faces with two equivalent Nd(5)Nd10Mg2 cuboctahedra, faces with four equivalent Nd(4)Nd10Mg2 cuboctahedra, faces with four equivalent Nd(1)Nd12 cuboctahedra, and faces with six equivalent Nd(2)Nd8Mg4 cuboctahedra. Both Nd(4)-Nd(4) bond lengths are 3.70 Å. Both Nd(4)-Nd(5) bond lengths are 3.74 Å. In the fifth Nd site, Nd(5) is bonded to two equivalent Mg(1), two equivalent Nd(1), two equivalent Nd(4), two equivalent Nd(5), and four equivalent Nd(3) atoms to form distorted NdNd10Mg2 cuboctahedra that share corners with six equivalent Nd(4)Nd10Mg2 cuboctahedra, corners with six equivalent Nd(5)Nd10Mg2 cuboctahedra, edges with three equivalent Nd(4)Nd10Mg2 cuboctahedra, edges with four equivalent Nd(3)Nd10Mg2 cuboctahedra, edges with eight equivalent Nd(2)Nd8Mg4 cuboctahedra, faces with two equivalent Nd(4)Nd10Mg2 cuboctahedra, faces with two equivalent Nd(2)Nd8Mg4 cuboctahedra, faces with four equivalent Nd(3)Nd10Mg2 cuboctahedra, faces with four equivalent Nd(5)Nd10Mg2 cuboctahedra, and faces with six equivalent Nd(1)Nd12 cuboctahedra. Both Nd(5)-Nd(5) bond lengths are 3.70 Å.