TlNbO3 crystallizes in the monoclinic Cc space group. There are four inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to one O(12), one O(2), one O(3), one O(4), one O(6), and one O(9) atom to form corner-sharing NbO6 octahedra. The corner-sharing octahedral tilt angles range from 36-42°. In the second Nb site, Nb(2) is bonded to one O(1), one O(10), one O(12), one O(4), one O(5), and one O(8) atom to form corner-sharing NbO6 octahedra. The corner-sharing octahedral tilt angles range from 36-42°. In the third Nb site, Nb(3) is bonded to one O(1), one O(10), one O(11), one O(6), one O(7), and one O(9) atom to form corner-sharing NbO6 octahedra. The corner-sharing octahedral tilt angles range from 36-42°. In the fourth Nb site, Nb(4) is bonded to one O(11), one O(2), one O(3), one O(5), one O(7), and one O(8) atom to form corner-sharing NbO6 octahedra. The corner-sharing octahedral tilt angles range from 36-42°. There are four inequivalent Tl sites. In the first Tl site, Tl(1) is bonded in a 3-coordinate geometry to one O(1), one O(5), and one O(7) atom. In the second Tl site, Tl(2) is bonded in a 5-coordinate geometry to one O(11), one O(3), one O(6), one O(7), and one O(9) atom. In the third Tl site, Tl(3) is bonded in a 3-coordinate geometry to one O(2), one O(4), and one O(8) atom. In the fourth Tl site, Tl(4) is bonded in a 6-coordinate geometry to one O(1), one O(10), one O(12), one O(4), one O(6), and one O(9) atom. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 150 degrees geometry to one Nb(2), one Nb(3), one Tl(1), and one Tl(4) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Nb(1), one Nb(4), and one Tl(3) atom. In the third O site, O(3) is bonded in a distorted bent 150 degrees geometry to one Nb(1), one Nb(4), and one Tl(2) atom. In the fourth O site, O(4) is bonded in a 2-coordinate geometry to one Nb(1), one Nb(2), one Tl(3), and one Tl(4) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Nb(2), one Nb(4), and one Tl(1) atom. In the sixth O site, O(6) is bonded in a 2-coordinate geometry to one Nb(1), one Nb(3), one Tl(2), and one Tl(4) atom. In the seventh O site, O(7) is bonded in a 4-coordinate geometry to one Nb(3), one Nb(4), one Tl(1), and one Tl(2) atom. In the eighth O site, O(8) is bonded in a 2-coordinate geometry to one Nb(2), one Nb(4), and one Tl(3) atom. In the ninth O site, O(9) is bonded in a 2-coordinate geometry to one Nb(1), one Nb(3), one Tl(2), and one Tl(4) atom. In the tenth O site, O(10) is bonded in a distorted bent 150 degrees geometry to one Nb(2), one Nb(3), and one Tl(4) atom. In the eleventh O site, O(11) is bonded in a 3-coordinate geometry to one Nb(3), one Nb(4), and one Tl(2) atom. In the twelfth O site, O(12) is bonded in a 2-coordinate geometry to one Nb(1), one Nb(2), and one Tl(4) atom.
TlNbO3 crystallizes in the monoclinic Cc space group. There are four inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to one O(12), one O(2), one O(3), one O(4), one O(6), and one O(9) atom to form corner-sharing NbO6 octahedra. The corner-sharing octahedral tilt angles range from 36-42°. The Nb(1)-O(12) bond length is 2.10 Å. The Nb(1)-O(2) bond length is 1.95 Å. The Nb(1)-O(3) bond length is 2.06 Å. The Nb(1)-O(4) bond length is 1.96 Å. The Nb(1)-O(6) bond length is 2.11 Å. The Nb(1)-O(9) bond length is 1.94 Å. In the second Nb site, Nb(2) is bonded to one O(1), one O(10), one O(12), one O(4), one O(5), and one O(8) atom to form corner-sharing NbO6 octahedra. The corner-sharing octahedral tilt angles range from 36-42°. The Nb(2)-O(1) bond length is 2.09 Å. The Nb(2)-O(10) bond length is 1.94 Å. The Nb(2)-O(12) bond length is 1.95 Å. The Nb(2)-O(4) bond length is 2.11 Å. The Nb(2)-O(5) bond length is 1.94 Å. The Nb(2)-O(8) bond length is 2.09 Å. In the third Nb site, Nb(3) is bonded to one O(1), one O(10), one O(11), one O(6), one O(7), and one O(9) atom to form corner-sharing NbO6 octahedra. The corner-sharing octahedral tilt angles range from 36-42°. The Nb(3)-O(1) bond length is 1.95 Å. The Nb(3)-O(10) bond length is 2.07 Å. The Nb(3)-O(11) bond length is 2.08 Å. The Nb(3)-O(6) bond length is 1.93 Å. The Nb(3)-O(7) bond length is 1.97 Å. The Nb(3)-O(9) bond length is 2.11 Å. In the fourth Nb site, Nb(4) is bonded to one O(11), one O(2), one O(3), one O(5), one O(7), and one O(8) atom to form corner-sharing NbO6 octahedra. The corner-sharing octahedral tilt angles range from 36-42°. The Nb(4)-O(11) bond length is 1.96 Å. The Nb(4)-O(2) bond length is 2.06 Å. The Nb(4)-O(3) bond length is 1.94 Å. The Nb(4)-O(5) bond length is 2.10 Å. The Nb(4)-O(7) bond length is 2.12 Å. The Nb(4)-O(8) bond length is 1.93 Å. There are four inequivalent Tl sites. In the first Tl site, Tl(1) is bonded in a 3-coordinate geometry to one O(1), one O(5), and one O(7) atom. The Tl(1)-O(1) bond length is 2.74 Å. The Tl(1)-O(5) bond length is 2.68 Å. The Tl(1)-O(7) bond length is 2.67 Å. In the second Tl site, Tl(2) is bonded in a 5-coordinate geometry to one O(11), one O(3), one O(6), one O(7), and one O(9) atom. The Tl(2)-O(11) bond length is 2.63 Å. The Tl(2)-O(3) bond length is 2.82 Å. The Tl(2)-O(6) bond length is 2.86 Å. The Tl(2)-O(7) bond length is 2.76 Å. The Tl(2)-O(9) bond length is 2.71 Å. In the third Tl site, Tl(3) is bonded in a 3-coordinate geometry to one O(2), one O(4), and one O(8) atom. The Tl(3)-O(2) bond length is 2.68 Å. The Tl(3)-O(4) bond length is 2.67 Å. The Tl(3)-O(8) bond length is 2.70 Å. In the fourth Tl site, Tl(4) is bonded in a 6-coordinate geometry to one O(1), one O(10), one O(12), one O(4), one O(6), and one O(9) atom. The Tl(4)-O(1) bond length is 2.80 Å. The Tl(4)-O(10) bond length is 2.79 Å. The Tl(4)-O(12) bond length is 2.70 Å. The Tl(4)-O(4) bond length is 2.87 Å. The Tl(4)-O(6) bond length is 2.73 Å. The Tl(4)-O(9) bond length is 2.83 Å. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 150 degrees geometry to one Nb(2), one Nb(3), one Tl(1), and one Tl(4) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Nb(1), one Nb(4), and one Tl(3) atom. In the third O site, O(3) is bonded in a distorted bent 150 degrees geometry to one Nb(1), one Nb(4), and one Tl(2) atom. In the fourth O site, O(4) is bonded in a 2-coordinate geometry to one Nb(1), one Nb(2), one Tl(3), and one Tl(4) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Nb(2), one Nb(4), and one Tl(1) atom. In the sixth O site, O(6) is bonded in a 2-coordinate geometry to one Nb(1), one Nb(3), one Tl(2), and one Tl(4) atom. In the seventh O site, O(7) is bonded in a 4-coordinate geometry to one Nb(3), one Nb(4), one Tl(1), and one Tl(2) atom. In the eighth O site, O(8) is bonded in a 2-coordinate geometry to one Nb(2), one Nb(4), and one Tl(3) atom. In the ninth O site, O(9) is bonded in a 2-coordinate geometry to one Nb(1), one Nb(3), one Tl(2), and one Tl(4) atom. In the tenth O site, O(10) is bonded in a distorted bent 150 degrees geometry to one Nb(2), one Nb(3), and one Tl(4) atom. In the eleventh O site, O(11) is bonded in a 3-coordinate geometry to one Nb(3), one Nb(4), and one Tl(2) atom. In the twelfth O site, O(12) is bonded in a 2-coordinate geometry to one Nb(1), one Nb(2), and one Tl(4) atom.