K2UF6 crystallizes in the orthorhombic Immm space group. K(1) is bonded in a body-centered cubic geometry to two equivalent F(2) and six equivalent F(1) atoms. U(1) is bonded in a body-centered cubic geometry to four equivalent F(1) and four equivalent F(2) atoms. There are two inequivalent F sites. In the first F site, F(1) is bonded to three equivalent K(1) and one U(1) atom to form FK3U tetrahedra that share corners with six equivalent F(2)K2U2 tetrahedra, corners with ten equivalent F(1)K3U tetrahedra, edges with two equivalent F(2)K2U2 tetrahedra, and edges with four equivalent F(1)K3U tetrahedra. In the second F site, F(2) is bonded to two equivalent K(1) and two equivalent U(1) atoms to form FK2U2 tetrahedra that share corners with four equivalent F(2)K2U2 tetrahedra, corners with twelve equivalent F(1)K3U tetrahedra, edges with two equivalent F(2)K2U2 tetrahedra, and edges with four equivalent F(1)K3U tetrahedra.
K2UF6 crystallizes in the orthorhombic Immm space group. K(1) is bonded in a body-centered cubic geometry to two equivalent F(2) and six equivalent F(1) atoms. Both K(1)-F(2) bond lengths are 2.73 Å. There are four shorter (2.67 Å) and two longer (2.72 Å) K(1)-F(1) bond lengths. U(1) is bonded in a body-centered cubic geometry to four equivalent F(1) and four equivalent F(2) atoms. All U(1)-F(1) bond lengths are 2.21 Å. All U(1)-F(2) bond lengths are 2.40 Å. There are two inequivalent F sites. In the first F site, F(1) is bonded to three equivalent K(1) and one U(1) atom to form FK3U tetrahedra that share corners with six equivalent F(2)K2U2 tetrahedra, corners with ten equivalent F(1)K3U tetrahedra, edges with two equivalent F(2)K2U2 tetrahedra, and edges with four equivalent F(1)K3U tetrahedra. In the second F site, F(2) is bonded to two equivalent K(1) and two equivalent U(1) atoms to form FK2U2 tetrahedra that share corners with four equivalent F(2)K2U2 tetrahedra, corners with twelve equivalent F(1)K3U tetrahedra, edges with two equivalent F(2)K2U2 tetrahedra, and edges with four equivalent F(1)K3U tetrahedra.