Nd5Mn8(PbO8)3 crystallizes in the cubic Pm-3m space group. There are three inequivalent Nd sites. In the first Nd site, Nd(1) is bonded to twelve equivalent O(2) atoms to form NdO12 cuboctahedra that share corners with twelve equivalent Nd(2)O12 cuboctahedra, faces with six equivalent Pb(1)O12 cuboctahedra, and faces with eight equivalent Mn(1)O6 octahedra. In the second Nd site, Nd(2) is bonded to four equivalent O(2) and eight equivalent O(1) atoms to form NdO12 cuboctahedra that share corners with four equivalent Nd(1)O12 cuboctahedra, corners with eight equivalent Nd(2)O12 cuboctahedra, faces with two equivalent Nd(3)O12 cuboctahedra, faces with four equivalent Pb(1)O12 cuboctahedra, and faces with eight equivalent Mn(1)O6 octahedra. In the third Nd site, Nd(3) is bonded to twelve equivalent O(1) atoms to form NdO12 cuboctahedra that share corners with twelve equivalent Pb(1)O12 cuboctahedra, faces with six equivalent Nd(2)O12 cuboctahedra, and faces with eight equivalent Mn(1)O6 octahedra. Mn(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form MnO6 octahedra that share corners with six equivalent Mn(1)O6 octahedra,  a faceface with one Nd(1)O12 cuboctahedra,  a faceface with one Nd(3)O12 cuboctahedra, faces with three equivalent Nd(2)O12 cuboctahedra, and faces with three equivalent Pb(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 1-5°. Pb(1) is bonded to four equivalent O(1) and eight equivalent O(2) atoms to form distorted PbO12 cuboctahedra that share corners with four equivalent Nd(3)O12 cuboctahedra, corners with eight equivalent Pb(1)O12 cuboctahedra, faces with two equivalent Nd(1)O12 cuboctahedra, faces with four equivalent Nd(2)O12 cuboctahedra, and faces with eight equivalent Mn(1)O6 octahedra. There are two inequivalent O sites. In the first O site, O(1) is bonded in a distorted linear geometry to one Nd(3), two equivalent Nd(2), two equivalent Mn(1), and one Pb(1) atom. In the second O site, O(2) is bonded in a distorted linear geometry to one Nd(1), one Nd(2), two equivalent Mn(1), and two equivalent Pb(1) atoms.
Nd5Mn8(PbO8)3 crystallizes in the cubic Pm-3m space group. There are three inequivalent Nd sites. In the first Nd site, Nd(1) is bonded to twelve equivalent O(2) atoms to form NdO12 cuboctahedra that share corners with twelve equivalent Nd(2)O12 cuboctahedra, faces with six equivalent Pb(1)O12 cuboctahedra, and faces with eight equivalent Mn(1)O6 octahedra. All Nd(1)-O(2) bond lengths are 2.79 Å. In the second Nd site, Nd(2) is bonded to four equivalent O(2) and eight equivalent O(1) atoms to form NdO12 cuboctahedra that share corners with four equivalent Nd(1)O12 cuboctahedra, corners with eight equivalent Nd(2)O12 cuboctahedra, faces with two equivalent Nd(3)O12 cuboctahedra, faces with four equivalent Pb(1)O12 cuboctahedra, and faces with eight equivalent Mn(1)O6 octahedra. All Nd(2)-O(2) bond lengths are 2.74 Å. All Nd(2)-O(1) bond lengths are 2.77 Å. In the third Nd site, Nd(3) is bonded to twelve equivalent O(1) atoms to form NdO12 cuboctahedra that share corners with twelve equivalent Pb(1)O12 cuboctahedra, faces with six equivalent Nd(2)O12 cuboctahedra, and faces with eight equivalent Mn(1)O6 octahedra. All Nd(3)-O(1) bond lengths are 2.67 Å. Mn(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form MnO6 octahedra that share corners with six equivalent Mn(1)O6 octahedra,  a faceface with one Nd(1)O12 cuboctahedra,  a faceface with one Nd(3)O12 cuboctahedra, faces with three equivalent Nd(2)O12 cuboctahedra, and faces with three equivalent Pb(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 1-5°. All Mn(1)-O(1) bond lengths are 1.95 Å. All Mn(1)-O(2) bond lengths are 1.96 Å. Pb(1) is bonded to four equivalent O(1) and eight equivalent O(2) atoms to form distorted PbO12 cuboctahedra that share corners with four equivalent Nd(3)O12 cuboctahedra, corners with eight equivalent Pb(1)O12 cuboctahedra, faces with two equivalent Nd(1)O12 cuboctahedra, faces with four equivalent Nd(2)O12 cuboctahedra, and faces with eight equivalent Mn(1)O6 octahedra. All Pb(1)-O(1) bond lengths are 2.85 Å. All Pb(1)-O(2) bond lengths are 2.76 Å. There are two inequivalent O sites. In the first O site, O(1) is bonded in a distorted linear geometry to one Nd(3), two equivalent Nd(2), two equivalent Mn(1), and one Pb(1) atom. In the second O site, O(2) is bonded in a distorted linear geometry to one Nd(1), one Nd(2), two equivalent Mn(1), and two equivalent Pb(1) atoms.