Cs8Ta6O19 crystallizes in the tetragonal I4/m space group. Cs(1) is bonded in a 6-coordinate geometry to one O(2), one O(3), two equivalent O(1), and two equivalent O(4) atoms. There are five inequivalent Ta sites. In the first Ta site, Ta(1) is bonded in a 6-coordinate geometry to one O(1), one O(5), two equivalent O(3), and two equivalent O(4) atoms. In the second Ta site, Ta(1) is bonded in a 6-coordinate geometry to one O(1), one O(5), two equivalent O(3), and two equivalent O(4) atoms. In the third Ta site, Ta(1) is bonded in a 6-coordinate geometry to one O(1), one O(5), two equivalent O(3), and two equivalent O(4) atoms. In the fourth Ta site, Ta(2) is bonded in a 6-coordinate geometry to one O(2), one O(5), and four equivalent O(4) atoms. In the fifth Ta site, Ta(1) is bonded in a 6-coordinate geometry to one O(1), one O(5), two equivalent O(3), and two equivalent O(4) atoms. There are five inequivalent O sites. In the first O site, O(2) is bonded in a distorted single-bond geometry to four equivalent Cs(1) and one Ta(2) atom. In the second O site, O(3) is bonded in a distorted bent 120 degrees geometry to two equivalent Cs(1) and two equivalent Ta(1) atoms. In the third O site, O(4) is bonded in a distorted bent 120 degrees geometry to two equivalent Cs(1), one Ta(1), and one Ta(2) atom. In the fourth O site, O(5) is bonded in an octahedral geometry to two equivalent Ta(2) and four Ta(1,1,1) atoms. In the fifth O site, O(1) is bonded in a distorted single-bond geometry to four equivalent Cs(1) and one Ta(1) atom.
Cs8Ta6O19 crystallizes in the tetragonal I4/m space group. Cs(1) is bonded in a 6-coordinate geometry to one O(2), one O(3), two equivalent O(1), and two equivalent O(4) atoms. The Cs(1)-O(2) bond length is 3.05 Å. The Cs(1)-O(3) bond length is 2.91 Å. There is one shorter (2.99 Å) and one longer (3.38 Å) Cs(1)-O(1) bond length. There is one shorter (3.15 Å) and one longer (3.29 Å) Cs(1)-O(4) bond length. There are five inequivalent Ta sites. In the first Ta site, Ta(1) is bonded in a 6-coordinate geometry to one O(1), one O(5), two equivalent O(3), and two equivalent O(4) atoms. The Ta(1)-O(1) bond length is 1.82 Å. The Ta(1)-O(5) bond length is 2.38 Å. There is one shorter (1.96 Å) and one longer (2.01 Å) Ta(1)-O(3) bond length. Both Ta(1)-O(4) bond lengths are 2.00 Å. In the second Ta site, Ta(1) is bonded in a 6-coordinate geometry to one O(1), one O(5), two equivalent O(3), and two equivalent O(4) atoms. The Ta(1)-O(1) bond length is 1.82 Å. The Ta(1)-O(5) bond length is 2.38 Å. There is one shorter (1.96 Å) and one longer (2.01 Å) Ta(1)-O(3) bond length. Both Ta(1)-O(4) bond lengths are 2.00 Å. In the third Ta site, Ta(1) is bonded in a 6-coordinate geometry to one O(1), one O(5), two equivalent O(3), and two equivalent O(4) atoms. The Ta(1)-O(1) bond length is 1.82 Å. The Ta(1)-O(5) bond length is 2.38 Å. There is one shorter (1.96 Å) and one longer (2.01 Å) Ta(1)-O(3) bond length. Both Ta(1)-O(4) bond lengths are 2.00 Å. In the fourth Ta site, Ta(2) is bonded in a 6-coordinate geometry to one O(2), one O(5), and four equivalent O(4) atoms. The Ta(2)-O(2) bond length is 1.82 Å. The Ta(2)-O(5) bond length is 2.34 Å. All Ta(2)-O(4) bond lengths are 2.00 Å. In the fifth Ta site, Ta(1) is bonded in a 6-coordinate geometry to one O(1), one O(5), two equivalent O(3), and two equivalent O(4) atoms. The Ta(1)-O(1) bond length is 1.82 Å. The Ta(1)-O(5) bond length is 2.38 Å. There is one shorter (1.96 Å) and one longer (2.01 Å) Ta(1)-O(3) bond length. Both Ta(1)-O(4) bond lengths are 2.00 Å. There are five inequivalent O sites. In the first O site, O(2) is bonded in a distorted single-bond geometry to four equivalent Cs(1) and one Ta(2) atom. In the second O site, O(3) is bonded in a distorted bent 120 degrees geometry to two equivalent Cs(1) and two equivalent Ta(1) atoms. In the third O site, O(4) is bonded in a distorted bent 120 degrees geometry to two equivalent Cs(1), one Ta(1), and one Ta(2) atom. In the fourth O site, O(5) is bonded in an octahedral geometry to two equivalent Ta(2) and four Ta(1,1,1) atoms. In the fifth O site, O(1) is bonded in a distorted single-bond geometry to four equivalent Cs(1) and one Ta(1) atom.