Pr11O20 crystallizes in the triclinic P-1 space group. There are six inequivalent Pr sites. In the first Pr site, Pr(1) is bonded in a body-centered cubic geometry to one O(1), one O(10), one O(2), one O(3), one O(4), one O(5), and two equivalent O(6) atoms. In the second Pr site, Pr(2) is bonded to one O(1), one O(10), one O(4), one O(5), one O(6), one O(8), and one O(9) atom to form a mixture of distorted corner and edge-sharing PrO7 hexagonal pyramids. In the third Pr site, Pr(3) is bonded in a 7-coordinate geometry to one O(1), one O(10), one O(6), two equivalent O(2), and two equivalent O(4) atoms. In the fourth Pr site, Pr(4) is bonded to one O(1), one O(3), one O(7), two equivalent O(8), and two equivalent O(9) atoms to form a mixture of distorted corner and edge-sharing PrO7 hexagonal pyramids. In the fifth Pr site, Pr(5) is bonded in a body-centered cubic geometry to two equivalent O(3), two equivalent O(5), two equivalent O(7), and two equivalent O(8) atoms. In the sixth Pr site, Pr(6) is bonded to one O(10), one O(2), one O(3), one O(5), one O(9), and two equivalent O(7) atoms to form a mixture of distorted corner and edge-sharing PrO7 hexagonal pyramids. There are ten inequivalent O sites. In the first O site, O(1) is bonded to one Pr(1), one Pr(2), one Pr(3), and one Pr(4) atom to form a mixture of corner and edge-sharing OPr4 tetrahedra. In the second O site, O(2) is bonded to one Pr(1), one Pr(6), and two equivalent Pr(3) atoms to form a mixture of corner and edge-sharing OPr4 tetrahedra. In the third O site, O(3) is bonded to one Pr(1), one Pr(4), one Pr(5), and one Pr(6) atom to form a mixture of corner and edge-sharing OPr4 tetrahedra. In the fourth O site, O(4) is bonded to one Pr(1), one Pr(2), and two equivalent Pr(3) atoms to form a mixture of corner and edge-sharing OPr4 tetrahedra. In the fifth O site, O(5) is bonded to one Pr(1), one Pr(2), one Pr(5), and one Pr(6) atom to form a mixture of corner and edge-sharing OPr4 tetrahedra. In the sixth O site, O(6) is bonded to one Pr(2), one Pr(3), and two equivalent Pr(1) atoms to form a mixture of corner and edge-sharing OPr4 tetrahedra. In the seventh O site, O(7) is bonded to one Pr(4), one Pr(5), and two equivalent Pr(6) atoms to form a mixture of corner and edge-sharing OPr4 tetrahedra. In the eighth O site, O(8) is bonded to one Pr(2), one Pr(5), and two equivalent Pr(4) atoms to form a mixture of corner and edge-sharing OPr4 tetrahedra. In the ninth O site, O(9) is bonded to one Pr(2), one Pr(6), and two equivalent Pr(4) atoms to form a mixture of corner and edge-sharing OPr4 tetrahedra. In the tenth O site, O(10) is bonded to one Pr(1), one Pr(2), one Pr(3), and one Pr(6) atom to form a mixture of corner and edge-sharing OPr4 tetrahedra.
Pr11O20 crystallizes in the triclinic P-1 space group. There are six inequivalent Pr sites. In the first Pr site, Pr(1) is bonded in a body-centered cubic geometry to one O(1), one O(10), one O(2), one O(3), one O(4), one O(5), and two equivalent O(6) atoms. The Pr(1)-O(1) bond length is 2.59 Å. The Pr(1)-O(10) bond length is 2.45 Å. The Pr(1)-O(2) bond length is 2.55 Å. The Pr(1)-O(3) bond length is 2.45 Å. The Pr(1)-O(4) bond length is 2.47 Å. The Pr(1)-O(5) bond length is 2.72 Å. There is one shorter (2.43 Å) and one longer (2.51 Å) Pr(1)-O(6) bond length. In the second Pr site, Pr(2) is bonded to one O(1), one O(10), one O(4), one O(5), one O(6), one O(8), and one O(9) atom to form a mixture of distorted corner and edge-sharing PrO7 hexagonal pyramids. The Pr(2)-O(1) bond length is 2.45 Å. The Pr(2)-O(10) bond length is 2.43 Å. The Pr(2)-O(4) bond length is 2.44 Å. The Pr(2)-O(5) bond length is 2.47 Å. The Pr(2)-O(6) bond length is 2.42 Å. The Pr(2)-O(8) bond length is 2.44 Å. The Pr(2)-O(9) bond length is 2.46 Å. In the third Pr site, Pr(3) is bonded in a 7-coordinate geometry to one O(1), one O(10), one O(6), two equivalent O(2), and two equivalent O(4) atoms. The Pr(3)-O(1) bond length is 2.44 Å. The Pr(3)-O(10) bond length is 2.41 Å. The Pr(3)-O(6) bond length is 2.45 Å. There is one shorter (2.46 Å) and one longer (2.48 Å) Pr(3)-O(2) bond length. There is one shorter (2.42 Å) and one longer (2.56 Å) Pr(3)-O(4) bond length. In the fourth Pr site, Pr(4) is bonded to one O(1), one O(3), one O(7), two equivalent O(8), and two equivalent O(9) atoms to form a mixture of distorted corner and edge-sharing PrO7 hexagonal pyramids. The Pr(4)-O(1) bond length is 2.49 Å. The Pr(4)-O(3) bond length is 2.43 Å. The Pr(4)-O(7) bond length is 2.42 Å. There is one shorter (2.39 Å) and one longer (2.44 Å) Pr(4)-O(8) bond length. There is one shorter (2.42 Å) and one longer (2.48 Å) Pr(4)-O(9) bond length. In the fifth Pr site, Pr(5) is bonded in a body-centered cubic geometry to two equivalent O(3), two equivalent O(5), two equivalent O(7), and two equivalent O(8) atoms. Both Pr(5)-O(3) bond lengths are 2.45 Å. Both Pr(5)-O(5) bond lengths are 2.53 Å. Both Pr(5)-O(7) bond lengths are 2.66 Å. Both Pr(5)-O(8) bond lengths are 2.43 Å. In the sixth Pr site, Pr(6) is bonded to one O(10), one O(2), one O(3), one O(5), one O(9), and two equivalent O(7) atoms to form a mixture of distorted corner and edge-sharing PrO7 hexagonal pyramids. The Pr(6)-O(10) bond length is 2.45 Å. The Pr(6)-O(2) bond length is 2.44 Å. The Pr(6)-O(3) bond length is 2.44 Å. The Pr(6)-O(5) bond length is 2.47 Å. The Pr(6)-O(9) bond length is 2.41 Å. Both Pr(6)-O(7) bond lengths are 2.46 Å. There are ten inequivalent O sites. In the first O site, O(1) is bonded to one Pr(1), one Pr(2), one Pr(3), and one Pr(4) atom to form a mixture of corner and edge-sharing OPr4 tetrahedra. In the second O site, O(2) is bonded to one Pr(1), one Pr(6), and two equivalent Pr(3) atoms to form a mixture of corner and edge-sharing OPr4 tetrahedra. In the third O site, O(3) is bonded to one Pr(1), one Pr(4), one Pr(5), and one Pr(6) atom to form a mixture of corner and edge-sharing OPr4 tetrahedra. In the fourth O site, O(4) is bonded to one Pr(1), one Pr(2), and two equivalent Pr(3) atoms to form a mixture of corner and edge-sharing OPr4 tetrahedra. In the fifth O site, O(5) is bonded to one Pr(1), one Pr(2), one Pr(5), and one Pr(6) atom to form a mixture of corner and edge-sharing OPr4 tetrahedra. In the sixth O site, O(6) is bonded to one Pr(2), one Pr(3), and two equivalent Pr(1) atoms to form a mixture of corner and edge-sharing OPr4 tetrahedra. In the seventh O site, O(7) is bonded to one Pr(4), one Pr(5), and two equivalent Pr(6) atoms to form a mixture of corner and edge-sharing OPr4 tetrahedra. In the eighth O site, O(8) is bonded to one Pr(2), one Pr(5), and two equivalent Pr(4) atoms to form a mixture of corner and edge-sharing OPr4 tetrahedra. In the ninth O site, O(9) is bonded to one Pr(2), one Pr(6), and two equivalent Pr(4) atoms to form a mixture of corner and edge-sharing OPr4 tetrahedra. In the tenth O site, O(10) is bonded to one Pr(1), one Pr(2), one Pr(3), and one Pr(6) atom to form a mixture of corner and edge-sharing OPr4 tetrahedra.