Pb5Ge3O12 crystallizes in the hexagonal P6_3/m space group. There are two inequivalent Pb sites. In the first Pb site, Pb(1) is bonded in a 6-coordinate geometry to three equivalent O(2) and three equivalent O(3) atoms. In the second Pb site, Pb(2) is bonded to one O(2) and four equivalent O(1) atoms to form distorted PbO5 trigonal bipyramids that share corners with three equivalent Ge(1)O4 tetrahedra, corners with four equivalent Pb(2)O5 trigonal bipyramids, and  an edgeedge with one Ge(1)O4 tetrahedra. Ge(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form GeO4 tetrahedra that share corners with three equivalent Pb(2)O5 trigonal bipyramids and  an edgeedge with one Pb(2)O5 trigonal bipyramid. There are three inequivalent O sites. In the first O site, O(3) is bonded in a 3-coordinate geometry to two equivalent Pb(1) and one Ge(1) atom. In the second O site, O(1) is bonded in a distorted single-bond geometry to two equivalent Pb(2) and one Ge(1) atom. In the third O site, O(2) is bonded in a 4-coordinate geometry to one Pb(2), two equivalent Pb(1), and one Ge(1) atom.
Pb5Ge3O12 crystallizes in the hexagonal P6_3/m space group. There are two inequivalent Pb sites. In the first Pb site, Pb(1) is bonded in a 6-coordinate geometry to three equivalent O(2) and three equivalent O(3) atoms. All Pb(1)-O(2) bond lengths are 2.73 Å. All Pb(1)-O(3) bond lengths are 2.43 Å. In the second Pb site, Pb(2) is bonded to one O(2) and four equivalent O(1) atoms to form distorted PbO5 trigonal bipyramids that share corners with three equivalent Ge(1)O4 tetrahedra, corners with four equivalent Pb(2)O5 trigonal bipyramids, and  an edgeedge with one Ge(1)O4 tetrahedra. The Pb(2)-O(2) bond length is 2.26 Å. There are two shorter (2.48 Å) and two longer (2.54 Å) Pb(2)-O(1) bond lengths. Ge(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form GeO4 tetrahedra that share corners with three equivalent Pb(2)O5 trigonal bipyramids and  an edgeedge with one Pb(2)O5 trigonal bipyramid. The Ge(1)-O(2) bond length is 1.80 Å. The Ge(1)-O(3) bond length is 1.78 Å. Both Ge(1)-O(1) bond lengths are 1.78 Å. There are three inequivalent O sites. In the first O site, O(3) is bonded in a 3-coordinate geometry to two equivalent Pb(1) and one Ge(1) atom. In the second O site, O(1) is bonded in a distorted single-bond geometry to two equivalent Pb(2) and one Ge(1) atom. In the third O site, O(2) is bonded in a 4-coordinate geometry to one Pb(2), two equivalent Pb(1), and one Ge(1) atom.