RbNbO3 crystallizes in the triclinic P-1 space group. There are three inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms. In the second Rb site, Rb(2) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(4), and two equivalent O(5) atoms. In the third Rb site, Rb(3) is bonded in a 8-coordinate geometry to one O(1), one O(3), one O(4), two equivalent O(5), and three equivalent O(2) atoms. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded in a 6-coordinate geometry to one O(1), one O(3), one O(4), one O(5), and two equivalent O(6) atoms. In the second Nb site, Nb(2) is bonded in a 6-coordinate geometry to one O(2), one O(3), one O(4), one O(5), and two equivalent O(6) atoms. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one Rb(1), one Rb(2), one Rb(3), and one Nb(1) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to one Rb(1), three equivalent Rb(3), and one Nb(2) atom. In the third O site, O(3) is bonded in a 2-coordinate geometry to one Rb(1), one Rb(3), one Nb(1), and one Nb(2) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Rb(2), one Rb(3), one Nb(1), and one Nb(2) atom. In the fifth O site, O(5) is bonded in a 2-coordinate geometry to one Rb(2), two equivalent Rb(3), one Nb(1), and one Nb(2) atom. In the sixth O site, O(6) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Nb(1) and two equivalent Nb(2) atoms.
RbNbO3 crystallizes in the triclinic P-1 space group. There are three inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms. Both Rb(1)-O(1) bond lengths are 2.98 Å. Both Rb(1)-O(2) bond lengths are 3.34 Å. Both Rb(1)-O(3) bond lengths are 2.81 Å. In the second Rb site, Rb(2) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(4), and two equivalent O(5) atoms. Both Rb(2)-O(1) bond lengths are 2.77 Å. Both Rb(2)-O(4) bond lengths are 2.78 Å. Both Rb(2)-O(5) bond lengths are 3.14 Å. In the third Rb site, Rb(3) is bonded in a 8-coordinate geometry to one O(1), one O(3), one O(4), two equivalent O(5), and three equivalent O(2) atoms. The Rb(3)-O(1) bond length is 2.84 Å. The Rb(3)-O(3) bond length is 3.30 Å. The Rb(3)-O(4) bond length is 3.06 Å. There is one shorter (3.01 Å) and one longer (3.31 Å) Rb(3)-O(5) bond length. There are a spread of Rb(3)-O(2) bond distances ranging from 2.86-3.03 Å. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded in a 6-coordinate geometry to one O(1), one O(3), one O(4), one O(5), and two equivalent O(6) atoms. The Nb(1)-O(1) bond length is 1.81 Å. The Nb(1)-O(3) bond length is 1.98 Å. The Nb(1)-O(4) bond length is 1.94 Å. The Nb(1)-O(5) bond length is 2.10 Å. There is one shorter (2.07 Å) and one longer (2.50 Å) Nb(1)-O(6) bond length. In the second Nb site, Nb(2) is bonded in a 6-coordinate geometry to one O(2), one O(3), one O(4), one O(5), and two equivalent O(6) atoms. The Nb(2)-O(2) bond length is 1.81 Å. The Nb(2)-O(3) bond length is 2.01 Å. The Nb(2)-O(4) bond length is 2.06 Å. The Nb(2)-O(5) bond length is 1.94 Å. There is one shorter (2.09 Å) and one longer (2.41 Å) Nb(2)-O(6) bond length. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one Rb(1), one Rb(2), one Rb(3), and one Nb(1) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to one Rb(1), three equivalent Rb(3), and one Nb(2) atom. In the third O site, O(3) is bonded in a 2-coordinate geometry to one Rb(1), one Rb(3), one Nb(1), and one Nb(2) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Rb(2), one Rb(3), one Nb(1), and one Nb(2) atom. In the fifth O site, O(5) is bonded in a 2-coordinate geometry to one Rb(2), two equivalent Rb(3), one Nb(1), and one Nb(2) atom. In the sixth O site, O(6) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Nb(1) and two equivalent Nb(2) atoms.