KNd(WO4)2 crystallizes in the monoclinic C2/m space group. K(1) is bonded in a 8-coordinate geometry to one O(2), one O(4), two equivalent O(1), two equivalent O(3), and two equivalent O(5) atoms. Nd(1) is bonded in a 8-coordinate geometry to two equivalent O(1), two equivalent O(2), two equivalent O(3), and two equivalent O(5) atoms. There are two inequivalent W sites. In the first W site, W(1) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form distorted edge-sharing WO6 octahedra. In the second W site, W(2) is bonded to one O(2), one O(4), two equivalent O(3), and two equivalent O(5) atoms to form distorted edge-sharing WO6 octahedra. There are five inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one K(1), one Nd(1), and one W(1) atom. In the second O site, O(2) is bonded to one K(1), two equivalent Nd(1), and one W(2) atom to form distorted OKNd2W tetrahedra that share corners with two equivalent O(4)KW3 tetrahedra and  an edgeedge with one O(2)KNd2W tetrahedra. In the third O site, O(3) is bonded in a 4-coordinate geometry to one K(1), one Nd(1), one W(1), and one W(2) atom. In the fourth O site, O(4) is bonded to one K(1), one W(2), and two equivalent W(1) atoms to form OKW3 tetrahedra that share corners with two equivalent O(2)KNd2W tetrahedra and  an edgeedge with one O(4)KW3 tetrahedra. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one K(1), one Nd(1), and one W(2) atom.
KNd(WO4)2 crystallizes in the monoclinic C2/m space group. K(1) is bonded in a 8-coordinate geometry to one O(2), one O(4), two equivalent O(1), two equivalent O(3), and two equivalent O(5) atoms. The K(1)-O(2) bond length is 2.69 Å. The K(1)-O(4) bond length is 2.57 Å. Both K(1)-O(1) bond lengths are 2.84 Å. Both K(1)-O(3) bond lengths are 2.97 Å. Both K(1)-O(5) bond lengths are 2.86 Å. Nd(1) is bonded in a 8-coordinate geometry to two equivalent O(1), two equivalent O(2), two equivalent O(3), and two equivalent O(5) atoms. Both Nd(1)-O(1) bond lengths are 2.46 Å. Both Nd(1)-O(2) bond lengths are 2.54 Å. Both Nd(1)-O(3) bond lengths are 2.46 Å. Both Nd(1)-O(5) bond lengths are 2.42 Å. There are two inequivalent W sites. In the first W site, W(1) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form distorted edge-sharing WO6 octahedra. Both W(1)-O(1) bond lengths are 1.78 Å. Both W(1)-O(3) bond lengths are 1.92 Å. Both W(1)-O(4) bond lengths are 2.19 Å. In the second W site, W(2) is bonded to one O(2), one O(4), two equivalent O(3), and two equivalent O(5) atoms to form distorted edge-sharing WO6 octahedra. The W(2)-O(2) bond length is 1.85 Å. The W(2)-O(4) bond length is 1.99 Å. Both W(2)-O(3) bond lengths are 2.15 Å. Both W(2)-O(5) bond lengths are 1.79 Å. There are five inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one K(1), one Nd(1), and one W(1) atom. In the second O site, O(2) is bonded to one K(1), two equivalent Nd(1), and one W(2) atom to form distorted OKNd2W tetrahedra that share corners with two equivalent O(4)KW3 tetrahedra and  an edgeedge with one O(2)KNd2W tetrahedra. In the third O site, O(3) is bonded in a 4-coordinate geometry to one K(1), one Nd(1), one W(1), and one W(2) atom. In the fourth O site, O(4) is bonded to one K(1), one W(2), and two equivalent W(1) atoms to form OKW3 tetrahedra that share corners with two equivalent O(2)KNd2W tetrahedra and  an edgeedge with one O(4)KW3 tetrahedra. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one K(1), one Nd(1), and one W(2) atom.