KNaNbOF5 crystallizes in the tetragonal P4/nmm space group. K(1) is bonded to four equivalent F(1) and eight equivalent F(2) atoms to form KF12 cuboctahedra that share corners with four equivalent K(1)F12 cuboctahedra, faces with four equivalent K(1)F12 cuboctahedra, faces with four equivalent Na(1)OF5 octahedra, and faces with four equivalent Nb(1)OF5 octahedra. Na(1) is bonded to one O(1), one F(1), and four equivalent F(2) atoms to form NaOF5 octahedra that share corners with six equivalent Nb(1)OF5 octahedra and faces with four equivalent K(1)F12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-19°. Nb(1) is bonded to one O(1), one F(1), and four equivalent F(2) atoms to form distorted NbOF5 octahedra that share corners with six equivalent Na(1)OF5 octahedra and faces with four equivalent K(1)F12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-19°. O(1) is bonded in a linear geometry to one Na(1) and one Nb(1) atom. There are two inequivalent F sites. In the first F site, F(1) is bonded in a distorted linear geometry to four equivalent K(1), one Na(1), and one Nb(1) atom. In the second F site, F(2) is bonded in a distorted rectangular see-saw-like geometry to two equivalent K(1), one Na(1), and one Nb(1) atom.
KNaNbOF5 crystallizes in the tetragonal P4/nmm space group. K(1) is bonded to four equivalent F(1) and eight equivalent F(2) atoms to form KF12 cuboctahedra that share corners with four equivalent K(1)F12 cuboctahedra, faces with four equivalent K(1)F12 cuboctahedra, faces with four equivalent Na(1)OF5 octahedra, and faces with four equivalent Nb(1)OF5 octahedra. All K(1)-F(1) bond lengths are 3.04 Å. All K(1)-F(2) bond lengths are 2.90 Å. Na(1) is bonded to one O(1), one F(1), and four equivalent F(2) atoms to form NaOF5 octahedra that share corners with six equivalent Nb(1)OF5 octahedra and faces with four equivalent K(1)F12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-19°. The Na(1)-O(1) bond length is 2.30 Å. The Na(1)-F(1) bond length is 2.40 Å. All Na(1)-F(2) bond lengths are 2.36 Å. Nb(1) is bonded to one O(1), one F(1), and four equivalent F(2) atoms to form distorted NbOF5 octahedra that share corners with six equivalent Na(1)OF5 octahedra and faces with four equivalent K(1)F12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-19°. The Nb(1)-O(1) bond length is 1.76 Å. The Nb(1)-F(1) bond length is 2.18 Å. All Nb(1)-F(2) bond lengths are 1.99 Å. O(1) is bonded in a linear geometry to one Na(1) and one Nb(1) atom. There are two inequivalent F sites. In the first F site, F(1) is bonded in a distorted linear geometry to four equivalent K(1), one Na(1), and one Nb(1) atom. In the second F site, F(2) is bonded in a distorted rectangular see-saw-like geometry to two equivalent K(1), one Na(1), and one Nb(1) atom.