Ba2ZnAlF9 crystallizes in the orthorhombic Pnma 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(3), three equivalent F(1), three equivalent F(6), and four equivalent F(4) atoms. In the second Ba site, Ba(2) is bonded in a 12-coordinate geometry to two equivalent F(4), two equivalent F(5), four equivalent F(2), and four equivalent F(3) atoms. Zn(1) is bonded to one F(5), one F(6), two equivalent F(2), and two equivalent F(3) atoms to form ZnF6 octahedra that share corners with three equivalent Al(1)F6 octahedra. The corner-sharing octahedral tilt angles range from 33-35°. Al(1) is bonded to one F(1), one F(5), two equivalent F(2), and two equivalent F(4) atoms to form AlF6 octahedra that share corners with three equivalent Zn(1)F6 octahedra. The corner-sharing octahedral tilt angles range from 33-35°. There are six inequivalent F sites. In the first F site, F(4) is bonded in a distorted single-bond geometry to one Ba(2), two equivalent Ba(1), and one Al(1) atom. In the second F site, F(5) is bonded in a 4-coordinate geometry to two equivalent Ba(2), one Zn(1), and one Al(1) atom. In the third F site, F(1) is bonded in a distorted single-bond geometry to three equivalent Ba(1) and one Al(1) atom. In the fourth F site, F(6) is bonded in a 2-coordinate geometry to three equivalent Ba(1) and one Zn(1) atom. In the fifth F site, F(2) is bonded in a distorted bent 150 degrees geometry to two equivalent Ba(2), one Zn(1), and one Al(1) atom. In the sixth F site, F(3) is bonded to one Ba(1), two equivalent Ba(2), and one Zn(1) atom to form a mixture of distorted edge and corner-sharing FBa3Zn tetrahedra.
Ba2ZnAlF9 crystallizes in the orthorhombic Pnma 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(3), three equivalent F(1), three equivalent F(6), and four equivalent F(4) atoms. Both Ba(1)-F(3) bond lengths are 2.80 Å. There is one shorter (2.83 Å) and two longer (3.31 Å) Ba(1)-F(1) bond lengths. There is one shorter (2.62 Å) and two longer (3.30 Å) Ba(1)-F(6) bond lengths. There are two shorter (2.91 Å) and two longer (3.01 Å) Ba(1)-F(4) bond lengths. In the second Ba site, Ba(2) is bonded in a 12-coordinate geometry to two equivalent F(4), two equivalent F(5), four equivalent F(2), and four equivalent F(3) atoms. Both Ba(2)-F(4) bond lengths are 2.78 Å. Both Ba(2)-F(5) bond lengths are 2.88 Å. There are two shorter (3.00 Å) and two longer (3.04 Å) Ba(2)-F(2) bond lengths. All Ba(2)-F(3) bond lengths are 2.72 Å. Zn(1) is bonded to one F(5), one F(6), two equivalent F(2), and two equivalent F(3) atoms to form ZnF6 octahedra that share corners with three equivalent Al(1)F6 octahedra. The corner-sharing octahedral tilt angles range from 33-35°. The Zn(1)-F(5) bond length is 2.25 Å. The Zn(1)-F(6) bond length is 1.95 Å. Both Zn(1)-F(2) bond lengths are 2.08 Å. Both Zn(1)-F(3) bond lengths are 2.02 Å. Al(1) is bonded to one F(1), one F(5), two equivalent F(2), and two equivalent F(4) atoms to form AlF6 octahedra that share corners with three equivalent Zn(1)F6 octahedra. The corner-sharing octahedral tilt angles range from 33-35°. The Al(1)-F(1) bond length is 1.79 Å. The Al(1)-F(5) bond length is 1.91 Å. Both Al(1)-F(2) bond lengths are 1.86 Å. Both Al(1)-F(4) bond lengths are 1.82 Å. There are six inequivalent F sites. In the first F site, F(4) is bonded in a distorted single-bond geometry to one Ba(2), two equivalent Ba(1), and one Al(1) atom. In the second F site, F(5) is bonded in a 4-coordinate geometry to two equivalent Ba(2), one Zn(1), and one Al(1) atom. In the third F site, F(1) is bonded in a distorted single-bond geometry to three equivalent Ba(1) and one Al(1) atom. In the fourth F site, F(6) is bonded in a 2-coordinate geometry to three equivalent Ba(1) and one Zn(1) atom. In the fifth F site, F(2) is bonded in a distorted bent 150 degrees geometry to two equivalent Ba(2), one Zn(1), and one Al(1) atom. In the sixth F site, F(3) is bonded to one Ba(1), two equivalent Ba(2), and one Zn(1) atom to form a mixture of distorted edge and corner-sharing FBa3Zn tetrahedra.