NaNb6O15F crystallizes in the orthorhombic Amm2 space group. Na(1) is bonded in a 9-coordinate geometry to one O(6), two equivalent O(2), two equivalent O(7), and four equivalent O(8) atoms. There are four inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to one O(3), one O(4), one O(5), one O(8), and two equivalent O(1) atoms to form NbO6 octahedra that share  a cornercorner with one Nb(3)O6 octahedra, corners with two equivalent Nb(2)O6 octahedra, corners with three equivalent Nb(1)O6 octahedra, and  an edgeedge with one Nb(4)O5F2 pentagonal bipyramid. The corner-sharing octahedral tilt angles range from 6-47°. In the second Nb site, Nb(2) is bonded to one O(2), one O(4), one O(5), one O(9), and two equivalent O(7) atoms to form distorted NbO6 octahedra that share  a cornercorner with one Nb(3)O6 octahedra, corners with two equivalent Nb(1)O6 octahedra, corners with three equivalent Nb(2)O6 octahedra, and  an edgeedge with one Nb(4)O5F2 pentagonal bipyramid. The corner-sharing octahedral tilt angles range from 15-42°. In the third Nb site, Nb(3) is bonded to two equivalent O(6), two equivalent O(8), and two equivalent O(9) atoms to form NbO6 octahedra that share corners with two equivalent Nb(1)O6 octahedra, corners with two equivalent Nb(2)O6 octahedra, corners with two equivalent Nb(3)O6 octahedra, and  an edgeedge with one Nb(4)O5F2 pentagonal bipyramid. The corner-sharing octahedral tilt angles range from 4-47°. In the fourth Nb site, Nb(4) is bonded to one O(3), two equivalent O(5), two equivalent O(9), and two equivalent F(1) atoms to form NbO5F2 pentagonal bipyramids that share corners with two equivalent Nb(4)O5F2 pentagonal bipyramids,  an edgeedge with one Nb(3)O6 octahedra, edges with two equivalent Nb(1)O6 octahedra, and edges with two equivalent Nb(2)O6 octahedra. There are nine inequivalent O sites. In the first O site, O(1) is bonded in a linear geometry to two equivalent Nb(1) atoms. In the second O site, O(2) is bonded to two equivalent Na(1) and two equivalent Nb(2) atoms to form distorted corner-sharing ONa2Nb2 tetrahedra. In the third O site, O(3) is bonded in a trigonal planar geometry to one Nb(4) and two equivalent Nb(1) atoms. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one Nb(1) and one Nb(2) atom. In the fifth O site, O(5) is bonded in a trigonal planar geometry to one Nb(1), one Nb(2), and one Nb(4) atom. In the sixth O site, O(6) is bonded in a distorted T-shaped geometry to one Na(1) and two equivalent Nb(3) atoms. In the seventh O site, O(7) is bonded in a distorted T-shaped geometry to one Na(1) and two equivalent Nb(2) atoms. In the eighth O site, O(8) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Na(1), one Nb(1), and one Nb(3) atom. In the ninth O site, O(9) is bonded in a distorted trigonal non-coplanar geometry to one Nb(2), one Nb(3), and one Nb(4) atom. F(1) is bonded in a linear geometry to two equivalent Nb(4) atoms.
NaNb6O15F crystallizes in the orthorhombic Amm2 space group. Na(1) is bonded in a 9-coordinate geometry to one O(6), two equivalent O(2), two equivalent O(7), and four equivalent O(8) atoms. The Na(1)-O(6) bond length is 2.72 Å. Both Na(1)-O(2) bond lengths are 2.56 Å. Both Na(1)-O(7) bond lengths are 2.75 Å. All Na(1)-O(8) bond lengths are 2.78 Å. There are four inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to one O(3), one O(4), one O(5), one O(8), and two equivalent O(1) atoms to form NbO6 octahedra that share  a cornercorner with one Nb(3)O6 octahedra, corners with two equivalent Nb(2)O6 octahedra, corners with three equivalent Nb(1)O6 octahedra, and  an edgeedge with one Nb(4)O5F2 pentagonal bipyramid. The corner-sharing octahedral tilt angles range from 6-47°. The Nb(1)-O(3) bond length is 2.08 Å. The Nb(1)-O(4) bond length is 1.95 Å. The Nb(1)-O(5) bond length is 2.17 Å. The Nb(1)-O(8) bond length is 1.93 Å. Both Nb(1)-O(1) bond lengths are 1.98 Å. In the second Nb site, Nb(2) is bonded to one O(2), one O(4), one O(5), one O(9), and two equivalent O(7) atoms to form distorted NbO6 octahedra that share  a cornercorner with one Nb(3)O6 octahedra, corners with two equivalent Nb(1)O6 octahedra, corners with three equivalent Nb(2)O6 octahedra, and  an edgeedge with one Nb(4)O5F2 pentagonal bipyramid. The corner-sharing octahedral tilt angles range from 15-42°. The Nb(2)-O(2) bond length is 2.00 Å. The Nb(2)-O(4) bond length is 1.91 Å. The Nb(2)-O(5) bond length is 2.06 Å. The Nb(2)-O(9) bond length is 2.26 Å. Both Nb(2)-O(7) bond lengths are 1.99 Å. In the third Nb site, Nb(3) is bonded to two equivalent O(6), two equivalent O(8), and two equivalent O(9) atoms to form NbO6 octahedra that share corners with two equivalent Nb(1)O6 octahedra, corners with two equivalent Nb(2)O6 octahedra, corners with two equivalent Nb(3)O6 octahedra, and  an edgeedge with one Nb(4)O5F2 pentagonal bipyramid. The corner-sharing octahedral tilt angles range from 4-47°. Both Nb(3)-O(6) bond lengths are 1.98 Å. Both Nb(3)-O(8) bond lengths are 2.00 Å. Both Nb(3)-O(9) bond lengths are 2.05 Å. In the fourth Nb site, Nb(4) is bonded to one O(3), two equivalent O(5), two equivalent O(9), and two equivalent F(1) atoms to form NbO5F2 pentagonal bipyramids that share corners with two equivalent Nb(4)O5F2 pentagonal bipyramids,  an edgeedge with one Nb(3)O6 octahedra, edges with two equivalent Nb(1)O6 octahedra, and edges with two equivalent Nb(2)O6 octahedra. The Nb(4)-O(3) bond length is 2.04 Å. Both Nb(4)-O(5) bond lengths are 2.07 Å. Both Nb(4)-O(9) bond lengths are 2.06 Å. Both Nb(4)-F(1) bond lengths are 1.98 Å. There are nine inequivalent O sites. In the first O site, O(1) is bonded in a linear geometry to two equivalent Nb(1) atoms. In the second O site, O(2) is bonded to two equivalent Na(1) and two equivalent Nb(2) atoms to form distorted corner-sharing ONa2Nb2 tetrahedra. In the third O site, O(3) is bonded in a trigonal planar geometry to one Nb(4) and two equivalent Nb(1) atoms. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one Nb(1) and one Nb(2) atom. In the fifth O site, O(5) is bonded in a trigonal planar geometry to one Nb(1), one Nb(2), and one Nb(4) atom. In the sixth O site, O(6) is bonded in a distorted T-shaped geometry to one Na(1) and two equivalent Nb(3) atoms. In the seventh O site, O(7) is bonded in a distorted T-shaped geometry to one Na(1) and two equivalent Nb(2) atoms. In the eighth O site, O(8) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Na(1), one Nb(1), and one Nb(3) atom. In the ninth O site, O(9) is bonded in a distorted trigonal non-coplanar geometry to one Nb(2), one Nb(3), and one Nb(4) atom. F(1) is bonded in a linear geometry to two equivalent Nb(4) atoms.