Ba2As6O11 crystallizes in the triclinic P1 space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 10-coordinate geometry to one O(1), one O(10), one O(11), one O(2), one O(4), one O(5), one O(7), one O(9), and two equivalent O(8) atoms. In the second Ba site, Ba(2) is bonded in a 10-coordinate geometry to one O(1), one O(10), one O(11), one O(2), one O(3), one O(6), one O(8), one O(9), and two equivalent O(7) atoms. There are six inequivalent As sites. In the first As site, As(1) is bonded in a distorted T-shaped geometry to one O(1), one O(5), and one O(9) atom. In the second As site, As(2) is bonded in a distorted T-shaped geometry to one O(10), one O(2), and one O(6) atom. In the third As site, As(3) is bonded in a distorted T-shaped geometry to one O(11), one O(4), and one O(5) atom. In the fourth As site, As(4) is bonded in a trigonal non-coplanar geometry to one O(3), one O(4), and one O(6) atom. In the fifth As site, As(5) is bonded in a distorted T-shaped geometry to one O(1), one O(7), and one O(9) atom. In the sixth As site, As(6) is bonded in a 3-coordinate geometry to one O(10), one O(2), and one O(8) atom. There are eleven inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 120 degrees geometry to one Ba(1), one Ba(2), one As(1), and one As(5) atom. In the second O site, O(2) is bonded in a distorted bent 120 degrees geometry to one Ba(1), one Ba(2), one As(2), and one As(6) atom. In the third O site, O(3) is bonded in a 2-coordinate geometry to one Ba(2) and one As(4) atom. In the fourth O site, O(4) is bonded in a distorted bent 120 degrees geometry to one Ba(1), one As(3), and one As(4) atom. In the fifth O site, O(5) is bonded in a distorted bent 120 degrees geometry to one Ba(1), one As(1), and one As(3) atom. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Ba(2), one As(2), and one As(4) atom. In the seventh O site, O(7) is bonded in a distorted single-bond geometry to one Ba(1), two equivalent Ba(2), and one As(5) atom. In the eighth O site, O(8) is bonded in a distorted single-bond geometry to one Ba(2), two equivalent Ba(1), and one As(6) atom. In the ninth O site, O(9) is bonded to one Ba(1), one Ba(2), one As(1), and one As(5) atom to form distorted edge-sharing OBa2As2 tetrahedra. In the tenth O site, O(10) is bonded to one Ba(1), one Ba(2), one As(2), and one As(6) atom to form distorted edge-sharing OBa2As2 tetrahedra. In the eleventh O site, O(11) is bonded in a distorted single-bond geometry to one Ba(1), one Ba(2), and one As(3) atom.
Ba2As6O11 crystallizes in the triclinic P1 space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 10-coordinate geometry to one O(1), one O(10), one O(11), one O(2), one O(4), one O(5), one O(7), one O(9), and two equivalent O(8) atoms. The Ba(1)-O(1) bond length is 2.94 Å. The Ba(1)-O(10) bond length is 2.93 Å. The Ba(1)-O(11) bond length is 2.95 Å. The Ba(1)-O(2) bond length is 3.19 Å. The Ba(1)-O(4) bond length is 3.10 Å. The Ba(1)-O(5) bond length is 2.90 Å. The Ba(1)-O(7) bond length is 2.75 Å. The Ba(1)-O(9) bond length is 2.81 Å. There is one shorter (2.90 Å) and one longer (2.97 Å) Ba(1)-O(8) bond length. In the second Ba site, Ba(2) is bonded in a 10-coordinate geometry to one O(1), one O(10), one O(11), one O(2), one O(3), one O(6), one O(8), one O(9), and two equivalent O(7) atoms. The Ba(2)-O(1) bond length is 3.02 Å. The Ba(2)-O(10) bond length is 2.93 Å. The Ba(2)-O(11) bond length is 2.86 Å. The Ba(2)-O(2) bond length is 2.98 Å. The Ba(2)-O(3) bond length is 2.75 Å. The Ba(2)-O(6) bond length is 2.91 Å. The Ba(2)-O(8) bond length is 2.74 Å. The Ba(2)-O(9) bond length is 2.92 Å. There is one shorter (2.82 Å) and one longer (2.91 Å) Ba(2)-O(7) bond length. There are six inequivalent As sites. In the first As site, As(1) is bonded in a distorted T-shaped geometry to one O(1), one O(5), and one O(9) atom. The As(1)-O(1) bond length is 1.81 Å. The As(1)-O(5) bond length is 1.80 Å. The As(1)-O(9) bond length is 1.80 Å. In the second As site, As(2) is bonded in a distorted T-shaped geometry to one O(10), one O(2), and one O(6) atom. The As(2)-O(10) bond length is 1.79 Å. The As(2)-O(2) bond length is 1.81 Å. The As(2)-O(6) bond length is 1.78 Å. In the third As site, As(3) is bonded in a distorted T-shaped geometry to one O(11), one O(4), and one O(5) atom. The As(3)-O(11) bond length is 1.70 Å. The As(3)-O(4) bond length is 1.84 Å. The As(3)-O(5) bond length is 1.86 Å. In the fourth As site, As(4) is bonded in a trigonal non-coplanar geometry to one O(3), one O(4), and one O(6) atom. The As(4)-O(3) bond length is 1.70 Å. The As(4)-O(4) bond length is 1.83 Å. The As(4)-O(6) bond length is 1.86 Å. In the fifth As site, As(5) is bonded in a distorted T-shaped geometry to one O(1), one O(7), and one O(9) atom. The As(5)-O(1) bond length is 1.87 Å. The As(5)-O(7) bond length is 1.70 Å. The As(5)-O(9) bond length is 1.90 Å. In the sixth As site, As(6) is bonded in a 3-coordinate geometry to one O(10), one O(2), and one O(8) atom. The As(6)-O(10) bond length is 1.90 Å. The As(6)-O(2) bond length is 1.89 Å. The As(6)-O(8) bond length is 1.70 Å. There are eleven inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 120 degrees geometry to one Ba(1), one Ba(2), one As(1), and one As(5) atom. In the second O site, O(2) is bonded in a distorted bent 120 degrees geometry to one Ba(1), one Ba(2), one As(2), and one As(6) atom. In the third O site, O(3) is bonded in a 2-coordinate geometry to one Ba(2) and one As(4) atom. In the fourth O site, O(4) is bonded in a distorted bent 120 degrees geometry to one Ba(1), one As(3), and one As(4) atom. In the fifth O site, O(5) is bonded in a distorted bent 120 degrees geometry to one Ba(1), one As(1), and one As(3) atom. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Ba(2), one As(2), and one As(4) atom. In the seventh O site, O(7) is bonded in a distorted single-bond geometry to one Ba(1), two equivalent Ba(2), and one As(5) atom. In the eighth O site, O(8) is bonded in a distorted single-bond geometry to one Ba(2), two equivalent Ba(1), and one As(6) atom. In the ninth O site, O(9) is bonded to one Ba(1), one Ba(2), one As(1), and one As(5) atom to form distorted edge-sharing OBa2As2 tetrahedra. In the tenth O site, O(10) is bonded to one Ba(1), one Ba(2), one As(2), and one As(6) atom to form distorted edge-sharing OBa2As2 tetrahedra. In the eleventh O site, O(11) is bonded in a distorted single-bond geometry to one Ba(1), one Ba(2), and one As(3) atom.