K2SbF5 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent K sites. In the first K site, K(1) is bonded to one F(1), one F(3), one F(4), one F(5), and two equivalent F(2) atoms to form distorted KF6 pentagonal pyramids that share corners with six equivalent Sb(1)F5 square pyramids and  an edgeedge with one K(1)F6 pentagonal pyramid. In the second K site, K(2) is bonded in a 9-coordinate geometry to one F(2), two equivalent F(1), two equivalent F(3), two equivalent F(4), and two equivalent F(5) atoms. Sb(1) is bonded to one F(1), one F(2), one F(3), one F(4), and one F(5) atom to form distorted SbF5 square pyramids that share corners with six equivalent K(1)F6 pentagonal pyramids. There are five inequivalent F sites. In the first F site, F(1) is bonded in a 4-coordinate geometry to one K(1), two equivalent K(2), and one Sb(1) atom. In the second F site, F(2) is bonded in a distorted see-saw-like geometry to one K(2), two equivalent K(1), and one Sb(1) atom. In the third F site, F(3) is bonded to one K(1), two equivalent K(2), and one Sb(1) atom to form a mixture of distorted corner and edge-sharing FK3Sb tetrahedra. In the fourth F site, F(4) is bonded in a 4-coordinate geometry to one K(1), two equivalent K(2), and one Sb(1) atom. In the fifth F site, F(5) is bonded to one K(1), two equivalent K(2), and one Sb(1) atom to form a mixture of distorted corner and edge-sharing FK3Sb tetrahedra.
K2SbF5 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent K sites. In the first K site, K(1) is bonded to one F(1), one F(3), one F(4), one F(5), and two equivalent F(2) atoms to form distorted KF6 pentagonal pyramids that share corners with six equivalent Sb(1)F5 square pyramids and  an edgeedge with one K(1)F6 pentagonal pyramid. The K(1)-F(1) bond length is 2.70 Å. The K(1)-F(3) bond length is 2.59 Å. The K(1)-F(4) bond length is 2.57 Å. The K(1)-F(5) bond length is 2.66 Å. There is one shorter (2.57 Å) and one longer (2.76 Å) K(1)-F(2) bond length. In the second K site, K(2) is bonded in a 9-coordinate geometry to one F(2), two equivalent F(1), two equivalent F(3), two equivalent F(4), and two equivalent F(5) atoms. The K(2)-F(2) bond length is 2.78 Å. There is one shorter (2.78 Å) and one longer (2.86 Å) K(2)-F(1) bond length. There is one shorter (2.79 Å) and one longer (2.85 Å) K(2)-F(3) bond length. There is one shorter (2.91 Å) and one longer (3.01 Å) K(2)-F(4) bond length. Both K(2)-F(5) bond lengths are 2.69 Å. Sb(1) is bonded to one F(1), one F(2), one F(3), one F(4), and one F(5) atom to form distorted SbF5 square pyramids that share corners with six equivalent K(1)F6 pentagonal pyramids. The Sb(1)-F(1) bond length is 1.97 Å. The Sb(1)-F(2) bond length is 2.12 Å. The Sb(1)-F(3) bond length is 2.06 Å. The Sb(1)-F(4) bond length is 2.11 Å. The Sb(1)-F(5) bond length is 2.06 Å. There are five inequivalent F sites. In the first F site, F(1) is bonded in a 4-coordinate geometry to one K(1), two equivalent K(2), and one Sb(1) atom. In the second F site, F(2) is bonded in a distorted see-saw-like geometry to one K(2), two equivalent K(1), and one Sb(1) atom. In the third F site, F(3) is bonded to one K(1), two equivalent K(2), and one Sb(1) atom to form a mixture of distorted corner and edge-sharing FK3Sb tetrahedra. In the fourth F site, F(4) is bonded in a 4-coordinate geometry to one K(1), two equivalent K(2), and one Sb(1) atom. In the fifth F site, F(5) is bonded to one K(1), two equivalent K(2), and one Sb(1) atom to form a mixture of distorted corner and edge-sharing FK3Sb tetrahedra.