Ba2MnNiF7Cl crystallizes in the monoclinic P2_1/m space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 12-coordinate geometry to two equivalent F(1), two equivalent F(4), four equivalent F(2), and four equivalent F(3) atoms. In the second Ba site, Ba(2) is bonded in a 9-coordinate geometry to three equivalent Cl(1), two equivalent F(3), and four equivalent F(1) atoms. Mn(1) is bonded to one Cl(1), one F(4), two equivalent F(1), and two equivalent F(2) atoms to form distorted MnClF5 octahedra that share corners with four equivalent Ni(1)ClF5 octahedra. The corner-sharing octahedral tilt angles range from 21-35°. Ni(1) is bonded to one Cl(1), one F(4), two equivalent F(2), and two equivalent F(3) atoms to form distorted NiClF5 octahedra that share corners with four equivalent Mn(1)ClF5 octahedra. The corner-sharing octahedral tilt angles range from 21-35°. Cl(1) is bonded in a 5-coordinate geometry to three equivalent Ba(2), one Mn(1), and one Ni(1) atom. There are four inequivalent F sites. In the first F site, F(1) is bonded to one Ba(1), two equivalent Ba(2), and one Mn(1) atom to form distorted FBa3Mn tetrahedra that share corners with two equivalent F(1)Ba3Mn tetrahedra, corners with six equivalent F(3)Ba3Ni tetrahedra,  an edgeedge with one F(3)Ba3Ni tetrahedra, and edges with three equivalent F(1)Ba3Mn tetrahedra. In the second F site, F(2) is bonded in a bent 150 degrees geometry to two equivalent Ba(1), one Mn(1), and one Ni(1) atom. In the third F site, F(3) is bonded to one Ba(2), two equivalent Ba(1), and one Ni(1) atom to form distorted FBa3Ni tetrahedra that share corners with two equivalent F(3)Ba3Ni tetrahedra, corners with six equivalent F(1)Ba3Mn tetrahedra,  an edgeedge with one F(1)Ba3Mn tetrahedra, and edges with three equivalent F(3)Ba3Ni tetrahedra. In the fourth F site, F(4) is bonded in a distorted bent 150 degrees geometry to two equivalent Ba(1), one Mn(1), and one Ni(1) atom.
Ba2MnNiF7Cl crystallizes in the monoclinic P2_1/m space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 12-coordinate geometry to two equivalent F(1), two equivalent F(4), four equivalent F(2), and four equivalent F(3) atoms. Both Ba(1)-F(1) bond lengths are 2.80 Å. Both Ba(1)-F(4) bond lengths are 2.98 Å. There are two shorter (3.12 Å) and two longer (3.18 Å) Ba(1)-F(2) bond lengths. There are two shorter (2.77 Å) and two longer (2.83 Å) Ba(1)-F(3) bond lengths. In the second Ba site, Ba(2) is bonded in a 9-coordinate geometry to three equivalent Cl(1), two equivalent F(3), and four equivalent F(1) atoms. There are two shorter (3.39 Å) and one longer (3.40 Å) Ba(2)-Cl(1) bond length. Both Ba(2)-F(3) bond lengths are 2.69 Å. All Ba(2)-F(1) bond lengths are 2.71 Å. Mn(1) is bonded to one Cl(1), one F(4), two equivalent F(1), and two equivalent F(2) atoms to form distorted MnClF5 octahedra that share corners with four equivalent Ni(1)ClF5 octahedra. The corner-sharing octahedral tilt angles range from 21-35°. The Mn(1)-Cl(1) bond length is 2.64 Å. The Mn(1)-F(4) bond length is 2.15 Å. Both Mn(1)-F(1) bond lengths are 2.12 Å. Both Mn(1)-F(2) bond lengths are 2.09 Å. Ni(1) is bonded to one Cl(1), one F(4), two equivalent F(2), and two equivalent F(3) atoms to form distorted NiClF5 octahedra that share corners with four equivalent Mn(1)ClF5 octahedra. The corner-sharing octahedral tilt angles range from 21-35°. The Ni(1)-Cl(1) bond length is 2.52 Å. The Ni(1)-F(4) bond length is 2.03 Å. Both Ni(1)-F(2) bond lengths are 2.01 Å. Both Ni(1)-F(3) bond lengths are 2.01 Å. Cl(1) is bonded in a 5-coordinate geometry to three equivalent Ba(2), one Mn(1), and one Ni(1) atom. There are four inequivalent F sites. In the first F site, F(1) is bonded to one Ba(1), two equivalent Ba(2), and one Mn(1) atom to form distorted FBa3Mn tetrahedra that share corners with two equivalent F(1)Ba3Mn tetrahedra, corners with six equivalent F(3)Ba3Ni tetrahedra,  an edgeedge with one F(3)Ba3Ni tetrahedra, and edges with three equivalent F(1)Ba3Mn tetrahedra. In the second F site, F(2) is bonded in a bent 150 degrees geometry to two equivalent Ba(1), one Mn(1), and one Ni(1) atom. In the third F site, F(3) is bonded to one Ba(2), two equivalent Ba(1), and one Ni(1) atom to form distorted FBa3Ni tetrahedra that share corners with two equivalent F(3)Ba3Ni tetrahedra, corners with six equivalent F(1)Ba3Mn tetrahedra,  an edgeedge with one F(1)Ba3Mn tetrahedra, and edges with three equivalent F(3)Ba3Ni tetrahedra. In the fourth F site, F(4) is bonded in a distorted bent 150 degrees geometry to two equivalent Ba(1), one Mn(1), and one Ni(1) atom.