Ba2Ni2F11 crystallizes in the trigonal P3_2 space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded to one F(1), one F(10), one F(11), one F(2), one F(3), one F(6), one F(7), one F(8), two equivalent F(4), and two equivalent F(5) atoms to form distorted BaF12 cuboctahedra that share  a cornercorner with one Ni(1)F6 octahedra, corners with three equivalent Ni(2)F6 octahedra, edges with two equivalent Ba(1)F12 cuboctahedra,  an edgeedge with one Ni(1)F6 octahedra,  an edgeedge with one Ni(2)F6 octahedra, and  a faceface with one Ni(1)F6 octahedra. The corner-sharing octahedral tilt angles range from 23-46°. In the second Ba site, Ba(2) is bonded in a 8-coordinate geometry to one F(1), one F(2), one F(3), one F(4), one F(5), one F(7), one F(8), and one F(9) atom. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one F(1), one F(2), one F(3), one F(4), one F(6), and one F(9) atom to form NiF6 octahedra that share  a cornercorner with one Ba(1)F12 cuboctahedra,  a cornercorner with one Ni(2)F6 octahedra,  an edgeedge with one Ba(1)F12 cuboctahedra,  an edgeedge with one Ni(2)F6 octahedra, and  a faceface with one Ba(1)F12 cuboctahedra. The corner-sharing octahedral tilt angles are 54°. In the second Ni site, Ni(2) is bonded to one F(1), one F(10), one F(11), one F(6), one F(8), and one F(9) atom to form NiF6 octahedra that share corners with three equivalent Ba(1)F12 cuboctahedra,  a cornercorner with one Ni(1)F6 octahedra,  an edgeedge with one Ba(1)F12 cuboctahedra, and  an edgeedge with one Ni(1)F6 octahedra. The corner-sharing octahedral tilt angles are 54°. There are eleven inequivalent F sites. In the first F site, F(11) is bonded in a distorted single-bond geometry to one Ba(1) and one Ni(2) atom. In the second F site, F(1) is bonded in a distorted water-like geometry to one Ba(1), one Ba(2), one Ni(1), and one Ni(2) atom. In the third F site, F(2) is bonded in a distorted single-bond geometry to one Ba(1), one Ba(2), and one Ni(1) atom. In the fourth F site, F(3) is bonded in a 3-coordinate geometry to one Ba(1), one Ba(2), and one Ni(1) atom. In the fifth F site, F(4) is bonded in a distorted single-bond geometry to one Ba(2), two equivalent Ba(1), and one Ni(1) atom. In the sixth F site, F(5) is bonded in a distorted trigonal planar geometry to one Ba(2) and two equivalent Ba(1) atoms. In the seventh F site, F(6) is bonded in a bent 120 degrees geometry to one Ba(1), one Ni(1), and one Ni(2) atom. In the eighth F site, F(7) is bonded in a water-like geometry to one Ba(1) and one Ba(2) atom. In the ninth F site, F(8) is bonded in a distorted trigonal non-coplanar geometry to one Ba(1), one Ba(2), and one Ni(2) atom. In the tenth F site, F(9) is bonded in a distorted water-like geometry to one Ba(2), one Ni(1), and one Ni(2) atom. In the eleventh F site, F(10) is bonded in a distorted single-bond geometry to one Ba(1) and one Ni(2) atom.
Ba2Ni2F11 crystallizes in the trigonal P3_2 space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded to one F(1), one F(10), one F(11), one F(2), one F(3), one F(6), one F(7), one F(8), two equivalent F(4), and two equivalent F(5) atoms to form distorted BaF12 cuboctahedra that share  a cornercorner with one Ni(1)F6 octahedra, corners with three equivalent Ni(2)F6 octahedra, edges with two equivalent Ba(1)F12 cuboctahedra,  an edgeedge with one Ni(1)F6 octahedra,  an edgeedge with one Ni(2)F6 octahedra, and  a faceface with one Ni(1)F6 octahedra. The corner-sharing octahedral tilt angles range from 23-46°. The Ba(1)-F(1) bond length is 3.12 Å. The Ba(1)-F(10) bond length is 2.88 Å. The Ba(1)-F(11) bond length is 2.70 Å. The Ba(1)-F(2) bond length is 2.73 Å. The Ba(1)-F(3) bond length is 2.77 Å. The Ba(1)-F(6) bond length is 3.13 Å. The Ba(1)-F(7) bond length is 2.93 Å. The Ba(1)-F(8) bond length is 2.83 Å. There is one shorter (2.75 Å) and one longer (3.04 Å) Ba(1)-F(4) bond length. There is one shorter (2.76 Å) and one longer (3.10 Å) Ba(1)-F(5) bond length. In the second Ba site, Ba(2) is bonded in a 8-coordinate geometry to one F(1), one F(2), one F(3), one F(4), one F(5), one F(7), one F(8), and one F(9) atom. The Ba(2)-F(1) bond length is 2.89 Å. The Ba(2)-F(2) bond length is 2.82 Å. The Ba(2)-F(3) bond length is 2.74 Å. The Ba(2)-F(4) bond length is 2.81 Å. The Ba(2)-F(5) bond length is 2.59 Å. The Ba(2)-F(7) bond length is 2.70 Å. The Ba(2)-F(8) bond length is 2.81 Å. The Ba(2)-F(9) bond length is 2.86 Å. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one F(1), one F(2), one F(3), one F(4), one F(6), and one F(9) atom to form NiF6 octahedra that share  a cornercorner with one Ba(1)F12 cuboctahedra,  a cornercorner with one Ni(2)F6 octahedra,  an edgeedge with one Ba(1)F12 cuboctahedra,  an edgeedge with one Ni(2)F6 octahedra, and  a faceface with one Ba(1)F12 cuboctahedra. The corner-sharing octahedral tilt angles are 54°. The Ni(1)-F(1) bond length is 1.97 Å. The Ni(1)-F(2) bond length is 1.87 Å. The Ni(1)-F(3) bond length is 1.91 Å. The Ni(1)-F(4) bond length is 1.90 Å. The Ni(1)-F(6) bond length is 1.92 Å. The Ni(1)-F(9) bond length is 1.98 Å. In the second Ni site, Ni(2) is bonded to one F(1), one F(10), one F(11), one F(6), one F(8), and one F(9) atom to form NiF6 octahedra that share corners with three equivalent Ba(1)F12 cuboctahedra,  a cornercorner with one Ni(1)F6 octahedra,  an edgeedge with one Ba(1)F12 cuboctahedra, and  an edgeedge with one Ni(1)F6 octahedra. The corner-sharing octahedral tilt angles are 54°. The Ni(2)-F(1) bond length is 2.02 Å. The Ni(2)-F(10) bond length is 1.82 Å. The Ni(2)-F(11) bond length is 1.84 Å. The Ni(2)-F(6) bond length is 1.96 Å. The Ni(2)-F(8) bond length is 1.95 Å. The Ni(2)-F(9) bond length is 1.99 Å. There are eleven inequivalent F sites. In the first F site, F(11) is bonded in a distorted single-bond geometry to one Ba(1) and one Ni(2) atom. In the second F site, F(1) is bonded in a distorted water-like geometry to one Ba(1), one Ba(2), one Ni(1), and one Ni(2) atom. In the third F site, F(2) is bonded in a distorted single-bond geometry to one Ba(1), one Ba(2), and one Ni(1) atom. In the fourth F site, F(3) is bonded in a 3-coordinate geometry to one Ba(1), one Ba(2), and one Ni(1) atom. In the fifth F site, F(4) is bonded in a distorted single-bond geometry to one Ba(2), two equivalent Ba(1), and one Ni(1) atom. In the sixth F site, F(5) is bonded in a distorted trigonal planar geometry to one Ba(2) and two equivalent Ba(1) atoms. In the seventh F site, F(6) is bonded in a bent 120 degrees geometry to one Ba(1), one Ni(1), and one Ni(2) atom. In the eighth F site, F(7) is bonded in a water-like geometry to one Ba(1) and one Ba(2) atom. In the ninth F site, F(8) is bonded in a distorted trigonal non-coplanar geometry to one Ba(1), one Ba(2), and one Ni(2) atom. In the tenth F site, F(9) is bonded in a distorted water-like geometry to one Ba(2), one Ni(1), and one Ni(2) atom. In the eleventh F site, F(10) is bonded in a distorted single-bond geometry to one Ba(1) and one Ni(2) atom.