Nd4O4(GeO4) crystallizes in the orthorhombic Pnma space group. There are three inequivalent Nd sites. In the first Nd site, Nd(1) is bonded in a 7-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(6), and two equivalent O(5) atoms. In the second Nd site, Nd(2) is bonded in a 7-coordinate geometry to one O(1), one O(2), one O(3), and four equivalent O(4) atoms. In the third Nd site, Nd(3) is bonded to one O(1), one O(3), one O(6), and four equivalent O(5) atoms to form distorted NdO7 pentagonal bipyramids that share  a cornercorner with one Ge(1)O4 tetrahedra and edges with two equivalent Nd(3)O7 pentagonal bipyramids. Ge(1) is bonded to one O(2), one O(6), and two equivalent O(4) atoms to form GeO4 tetrahedra that share  a cornercorner with one Nd(3)O7 pentagonal bipyramid. There are six inequivalent O sites. In the first O site, O(1) is bonded to one Nd(2), one Nd(3), and two equivalent Nd(1) atoms to form ONd4 tetrahedra that share corners with four equivalent O(5)Nd4 tetrahedra, corners with three equivalent O(2)Nd3Ge trigonal pyramids, edges with two equivalent O(3)Nd4 tetrahedra, and edges with two equivalent O(5)Nd4 tetrahedra. In the second O site, O(2) is bonded to one Nd(2), two equivalent Nd(1), and one Ge(1) atom to form distorted corner-sharing ONd3Ge trigonal pyramids. In the third O site, O(3) is bonded to one Nd(2), one Nd(3), and two equivalent Nd(1) atoms to form ONd4 tetrahedra that share corners with four equivalent O(5)Nd4 tetrahedra, corners with three equivalent O(2)Nd3Ge trigonal pyramids, edges with two equivalent O(1)Nd4 tetrahedra, and edges with two equivalent O(5)Nd4 tetrahedra. In the fourth O site, O(4) is bonded in a distorted rectangular see-saw-like geometry to one Nd(1), two equivalent Nd(2), and one Ge(1) atom. In the fifth O site, O(5) is bonded to two equivalent Nd(1) and two equivalent Nd(3) atoms to form ONd4 tetrahedra that share corners with two equivalent O(1)Nd4 tetrahedra, corners with two equivalent O(3)Nd4 tetrahedra, corners with four equivalent O(5)Nd4 tetrahedra, corners with two equivalent O(2)Nd3Ge trigonal pyramids,  an edgeedge with one O(1)Nd4 tetrahedra,  an edgeedge with one O(3)Nd4 tetrahedra, and edges with two equivalent O(5)Nd4 tetrahedra. In the sixth O site, O(6) is bonded in a 4-coordinate geometry to one Nd(3), two equivalent Nd(1), and one Ge(1) atom.
Nd4O4(GeO4) crystallizes in the orthorhombic Pnma space group. There are three inequivalent Nd sites. In the first Nd site, Nd(1) is bonded in a 7-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(6), and two equivalent O(5) atoms. The Nd(1)-O(1) bond length is 2.36 Å. The Nd(1)-O(2) bond length is 2.55 Å. The Nd(1)-O(3) bond length is 2.33 Å. The Nd(1)-O(4) bond length is 2.85 Å. The Nd(1)-O(6) bond length is 2.55 Å. There is one shorter (2.32 Å) and one longer (2.34 Å) Nd(1)-O(5) bond length. In the second Nd site, Nd(2) is bonded in a 7-coordinate geometry to one O(1), one O(2), one O(3), and four equivalent O(4) atoms. The Nd(2)-O(1) bond length is 2.25 Å. The Nd(2)-O(2) bond length is 2.57 Å. The Nd(2)-O(3) bond length is 2.26 Å. There are two shorter (2.47 Å) and two longer (2.71 Å) Nd(2)-O(4) bond lengths. In the third Nd site, Nd(3) is bonded to one O(1), one O(3), one O(6), and four equivalent O(5) atoms to form distorted NdO7 pentagonal bipyramids that share  a cornercorner with one Ge(1)O4 tetrahedra and edges with two equivalent Nd(3)O7 pentagonal bipyramids. The Nd(3)-O(1) bond length is 2.45 Å. The Nd(3)-O(3) bond length is 2.35 Å. The Nd(3)-O(6) bond length is 2.56 Å. There are two shorter (2.38 Å) and two longer (2.45 Å) Nd(3)-O(5) bond lengths. Ge(1) is bonded to one O(2), one O(6), and two equivalent O(4) atoms to form GeO4 tetrahedra that share  a cornercorner with one Nd(3)O7 pentagonal bipyramid. The Ge(1)-O(2) bond length is 1.77 Å. The Ge(1)-O(6) bond length is 1.78 Å. Both Ge(1)-O(4) bond lengths are 1.77 Å. There are six inequivalent O sites. In the first O site, O(1) is bonded to one Nd(2), one Nd(3), and two equivalent Nd(1) atoms to form ONd4 tetrahedra that share corners with four equivalent O(5)Nd4 tetrahedra, corners with three equivalent O(2)Nd3Ge trigonal pyramids, edges with two equivalent O(3)Nd4 tetrahedra, and edges with two equivalent O(5)Nd4 tetrahedra. In the second O site, O(2) is bonded to one Nd(2), two equivalent Nd(1), and one Ge(1) atom to form distorted corner-sharing ONd3Ge trigonal pyramids. In the third O site, O(3) is bonded to one Nd(2), one Nd(3), and two equivalent Nd(1) atoms to form ONd4 tetrahedra that share corners with four equivalent O(5)Nd4 tetrahedra, corners with three equivalent O(2)Nd3Ge trigonal pyramids, edges with two equivalent O(1)Nd4 tetrahedra, and edges with two equivalent O(5)Nd4 tetrahedra. In the fourth O site, O(4) is bonded in a distorted rectangular see-saw-like geometry to one Nd(1), two equivalent Nd(2), and one Ge(1) atom. In the fifth O site, O(5) is bonded to two equivalent Nd(1) and two equivalent Nd(3) atoms to form ONd4 tetrahedra that share corners with two equivalent O(1)Nd4 tetrahedra, corners with two equivalent O(3)Nd4 tetrahedra, corners with four equivalent O(5)Nd4 tetrahedra, corners with two equivalent O(2)Nd3Ge trigonal pyramids,  an edgeedge with one O(1)Nd4 tetrahedra,  an edgeedge with one O(3)Nd4 tetrahedra, and edges with two equivalent O(5)Nd4 tetrahedra. In the sixth O site, O(6) is bonded in a 4-coordinate geometry to one Nd(3), two equivalent Nd(1), and one Ge(1) atom.