Rb2Th(AsO4)2 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a 8-coordinate geometry to one O(1), one O(4), one O(6), one O(8), two equivalent O(3), and two equivalent O(5) atoms. In the second Rb site, Rb(2) is bonded in a 9-coordinate geometry to one O(1), one O(3), one O(4), one O(6), one O(7), two equivalent O(2), and two equivalent O(8) atoms. Th(1) is bonded in a 8-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), one O(6), one O(7), and one O(8) atom. There are two inequivalent As sites. In the first As site, As(1) is bonded in a tetrahedral geometry to one O(1), one O(2), one O(3), and one O(6) atom. In the second As site, As(2) is bonded in a tetrahedral geometry to one O(4), one O(5), one O(7), and one O(8) atom. There are eight inequivalent O sites. In the first O site, O(4) is bonded in a 4-coordinate geometry to one Rb(1), one Rb(2), one Th(1), and one As(2) atom. In the second O site, O(5) is bonded in a 4-coordinate geometry to two equivalent Rb(1), one Th(1), and one As(2) atom. In the third O site, O(6) is bonded in a 2-coordinate geometry to one Rb(1), one Rb(2), one Th(1), and one As(1) atom. In the fourth O site, O(7) is bonded in a 3-coordinate geometry to one Rb(2), one Th(1), and one As(2) atom. In the fifth O site, O(8) is bonded in a 1-coordinate geometry to one Rb(1), two equivalent Rb(2), one Th(1), and one As(2) atom. In the sixth O site, O(1) is bonded in a 2-coordinate geometry to one Rb(1), one Rb(2), one Th(1), and one As(1) atom. In the seventh O site, O(2) is bonded in a distorted single-bond geometry to two equivalent Rb(2), one Th(1), and one As(1) atom. In the eighth O site, O(3) is bonded in a 1-coordinate geometry to one Rb(2), two equivalent Rb(1), one Th(1), and one As(1) atom.
Rb2Th(AsO4)2 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a 8-coordinate geometry to one O(1), one O(4), one O(6), one O(8), two equivalent O(3), and two equivalent O(5) atoms. The Rb(1)-O(1) bond length is 3.15 Å. The Rb(1)-O(4) bond length is 2.81 Å. The Rb(1)-O(6) bond length is 3.12 Å. The Rb(1)-O(8) bond length is 3.12 Å. There is one shorter (2.94 Å) and one longer (3.18 Å) Rb(1)-O(3) bond length. There is one shorter (2.84 Å) and one longer (2.92 Å) Rb(1)-O(5) bond length. In the second Rb site, Rb(2) is bonded in a 9-coordinate geometry to one O(1), one O(3), one O(4), one O(6), one O(7), two equivalent O(2), and two equivalent O(8) atoms. The Rb(2)-O(1) bond length is 3.16 Å. The Rb(2)-O(3) bond length is 2.82 Å. The Rb(2)-O(4) bond length is 2.91 Å. The Rb(2)-O(6) bond length is 3.42 Å. The Rb(2)-O(7) bond length is 2.96 Å. There is one shorter (2.84 Å) and one longer (3.21 Å) Rb(2)-O(2) bond length. There is one shorter (3.23 Å) and one longer (3.31 Å) Rb(2)-O(8) bond length. Th(1) is bonded in a 8-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), one O(6), one O(7), and one O(8) atom. The Th(1)-O(1) bond length is 2.43 Å. The Th(1)-O(2) bond length is 2.55 Å. The Th(1)-O(3) bond length is 2.54 Å. The Th(1)-O(4) bond length is 2.47 Å. The Th(1)-O(5) bond length is 2.52 Å. The Th(1)-O(6) bond length is 2.38 Å. The Th(1)-O(7) bond length is 2.42 Å. The Th(1)-O(8) bond length is 2.47 Å. There are two inequivalent As sites. In the first As site, As(1) is bonded in a tetrahedral geometry to one O(1), one O(2), one O(3), and one O(6) atom. The As(1)-O(1) bond length is 1.72 Å. The As(1)-O(2) bond length is 1.73 Å. The As(1)-O(3) bond length is 1.73 Å. The As(1)-O(6) bond length is 1.72 Å. In the second As site, As(2) is bonded in a tetrahedral geometry to one O(4), one O(5), one O(7), and one O(8) atom. The As(2)-O(4) bond length is 1.73 Å. The As(2)-O(5) bond length is 1.73 Å. The As(2)-O(7) bond length is 1.73 Å. The As(2)-O(8) bond length is 1.72 Å. There are eight inequivalent O sites. In the first O site, O(4) is bonded in a 4-coordinate geometry to one Rb(1), one Rb(2), one Th(1), and one As(2) atom. In the second O site, O(5) is bonded in a 4-coordinate geometry to two equivalent Rb(1), one Th(1), and one As(2) atom. In the third O site, O(6) is bonded in a 2-coordinate geometry to one Rb(1), one Rb(2), one Th(1), and one As(1) atom. In the fourth O site, O(7) is bonded in a 3-coordinate geometry to one Rb(2), one Th(1), and one As(2) atom. In the fifth O site, O(8) is bonded in a 1-coordinate geometry to one Rb(1), two equivalent Rb(2), one Th(1), and one As(2) atom. In the sixth O site, O(1) is bonded in a 2-coordinate geometry to one Rb(1), one Rb(2), one Th(1), and one As(1) atom. In the seventh O site, O(2) is bonded in a distorted single-bond geometry to two equivalent Rb(2), one Th(1), and one As(1) atom. In the eighth O site, O(3) is bonded in a 1-coordinate geometry to one Rb(2), two equivalent Rb(1), one Th(1), and one As(1) atom.