NaCaNb2O6F crystallizes in the orthorhombic Imma space group. Na(1) is bonded to two equivalent O(2), four equivalent O(1), and two equivalent F(1) atoms to form distorted NaO6F2 hexagonal bipyramids that share edges with two equivalent Na(1)O6F2 hexagonal bipyramids, edges with four equivalent Ca(1)O6F2 hexagonal bipyramids, edges with two equivalent Nb(2)O6 octahedra, and edges with four equivalent Nb(1)O6 octahedra. Ca(1) is bonded to two equivalent O(3), four equivalent O(1), and two equivalent F(1) atoms to form distorted CaO6F2 hexagonal bipyramids that share edges with two equivalent Ca(1)O6F2 hexagonal bipyramids, edges with four equivalent Na(1)O6F2 hexagonal bipyramids, edges with two equivalent Nb(1)O6 octahedra, and edges with four equivalent Nb(2)O6 octahedra. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form NbO6 octahedra that share corners with two equivalent Nb(1)O6 octahedra, corners with four equivalent Nb(2)O6 octahedra, edges with two equivalent Ca(1)O6F2 hexagonal bipyramids, and edges with four equivalent Na(1)O6F2 hexagonal bipyramids. The corner-sharing octahedral tilt angles range from 39-42°. In the second Nb site, Nb(2) is bonded to two equivalent O(3) and four equivalent O(1) atoms to form NbO6 octahedra that share corners with two equivalent Nb(2)O6 octahedra, corners with four equivalent Nb(1)O6 octahedra, edges with two equivalent Na(1)O6F2 hexagonal bipyramids, and edges with four equivalent Ca(1)O6F2 hexagonal bipyramids. The corner-sharing octahedral tilt angles range from 42-45°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Na(1), one Ca(1), one Nb(1), and one Nb(2) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to two equivalent Na(1) and two equivalent Nb(1) atoms. In the third O site, O(3) is bonded in a 4-coordinate geometry to two equivalent Ca(1) and two equivalent Nb(2) atoms. F(1) is bonded to two equivalent Na(1) and two equivalent Ca(1) atoms to form corner-sharing FNa2Ca2 tetrahedra.
NaCaNb2O6F crystallizes in the orthorhombic Imma space group. Na(1) is bonded to two equivalent O(2), four equivalent O(1), and two equivalent F(1) atoms to form distorted NaO6F2 hexagonal bipyramids that share edges with two equivalent Na(1)O6F2 hexagonal bipyramids, edges with four equivalent Ca(1)O6F2 hexagonal bipyramids, edges with two equivalent Nb(2)O6 octahedra, and edges with four equivalent Nb(1)O6 octahedra. Both Na(1)-O(2) bond lengths are 2.71 Å. All Na(1)-O(1) bond lengths are 2.72 Å. Both Na(1)-F(1) bond lengths are 2.32 Å. Ca(1) is bonded to two equivalent O(3), four equivalent O(1), and two equivalent F(1) atoms to form distorted CaO6F2 hexagonal bipyramids that share edges with two equivalent Ca(1)O6F2 hexagonal bipyramids, edges with four equivalent Na(1)O6F2 hexagonal bipyramids, edges with two equivalent Nb(1)O6 octahedra, and edges with four equivalent Nb(2)O6 octahedra. Both Ca(1)-O(3) bond lengths are 2.66 Å. All Ca(1)-O(1) bond lengths are 2.64 Å. Both Ca(1)-F(1) bond lengths are 2.26 Å. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form NbO6 octahedra that share corners with two equivalent Nb(1)O6 octahedra, corners with four equivalent Nb(2)O6 octahedra, edges with two equivalent Ca(1)O6F2 hexagonal bipyramids, and edges with four equivalent Na(1)O6F2 hexagonal bipyramids. The corner-sharing octahedral tilt angles range from 39-42°. Both Nb(1)-O(2) bond lengths are 2.00 Å. All Nb(1)-O(1) bond lengths are 2.01 Å. In the second Nb site, Nb(2) is bonded to two equivalent O(3) and four equivalent O(1) atoms to form NbO6 octahedra that share corners with two equivalent Nb(2)O6 octahedra, corners with four equivalent Nb(1)O6 octahedra, edges with two equivalent Na(1)O6F2 hexagonal bipyramids, and edges with four equivalent Ca(1)O6F2 hexagonal bipyramids. The corner-sharing octahedral tilt angles range from 42-45°. Both Nb(2)-O(3) bond lengths are 2.01 Å. All Nb(2)-O(1) bond lengths are 2.00 Å. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Na(1), one Ca(1), one Nb(1), and one Nb(2) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to two equivalent Na(1) and two equivalent Nb(1) atoms. In the third O site, O(3) is bonded in a 4-coordinate geometry to two equivalent Ca(1) and two equivalent Nb(2) atoms. F(1) is bonded to two equivalent Na(1) and two equivalent Ca(1) atoms to form corner-sharing FNa2Ca2 tetrahedra.