RbB3O5 crystallizes in the orthorhombic P2_12_12_1 space group. Rb(1) is bonded in a 9-coordinate geometry to two equivalent O(1), two equivalent O(2), two equivalent O(3), and three equivalent O(5) atoms. There are three inequivalent B sites. In the first B site, B(1) is bonded in a trigonal planar geometry to one O(2), one O(4), and one O(5) atom. In the second B site, B(2) is bonded in a tetrahedral geometry to one O(1), one O(2), one O(3), and one O(5) atom. In the third B site, B(3) is bonded in a trigonal planar geometry to one O(1), one O(3), and one O(4) atom. There are five inequivalent O sites. In the first O site, O(1) is bonded in a bent 120 degrees geometry to two equivalent Rb(1), one B(2), and one B(3) atom. In the second O site, O(2) is bonded in a distorted bent 120 degrees geometry to two equivalent Rb(1), one B(1), and one B(2) atom. In the third O site, O(3) is bonded in a distorted bent 120 degrees geometry to two equivalent Rb(1), one B(2), and one B(3) atom. In the fourth O site, O(4) is bonded in a bent 120 degrees geometry to one B(1) and one B(3) atom. In the fifth O site, O(5) is bonded in a bent 120 degrees geometry to three equivalent Rb(1), one B(1), and one B(2) atom.
RbB3O5 crystallizes in the orthorhombic P2_12_12_1 space group. Rb(1) is bonded in a 9-coordinate geometry to two equivalent O(1), two equivalent O(2), two equivalent O(3), and three equivalent O(5) atoms. Both Rb(1)-O(1) bond lengths are 2.99 Å. There is one shorter (2.83 Å) and one longer (3.15 Å) Rb(1)-O(2) bond length. There is one shorter (2.92 Å) and one longer (3.23 Å) Rb(1)-O(3) bond length. There are a spread of Rb(1)-O(5) bond distances ranging from 3.05-3.22 Å. There are three inequivalent B sites. In the first B site, B(1) is bonded in a trigonal planar geometry to one O(2), one O(4), and one O(5) atom. The B(1)-O(2) bond length is 1.37 Å. The B(1)-O(4) bond length is 1.39 Å. The B(1)-O(5) bond length is 1.37 Å. In the second B site, B(2) is bonded in a tetrahedral geometry to one O(1), one O(2), one O(3), and one O(5) atom. The B(2)-O(1) bond length is 1.47 Å. The B(2)-O(2) bond length is 1.48 Å. The B(2)-O(3) bond length is 1.47 Å. The B(2)-O(5) bond length is 1.47 Å. In the third B site, B(3) is bonded in a trigonal planar geometry to one O(1), one O(3), and one O(4) atom. The B(3)-O(1) bond length is 1.36 Å. The B(3)-O(3) bond length is 1.36 Å. The B(3)-O(4) bond length is 1.40 Å. There are five inequivalent O sites. In the first O site, O(1) is bonded in a bent 120 degrees geometry to two equivalent Rb(1), one B(2), and one B(3) atom. In the second O site, O(2) is bonded in a distorted bent 120 degrees geometry to two equivalent Rb(1), one B(1), and one B(2) atom. In the third O site, O(3) is bonded in a distorted bent 120 degrees geometry to two equivalent Rb(1), one B(2), and one B(3) atom. In the fourth O site, O(4) is bonded in a bent 120 degrees geometry to one B(1) and one B(3) atom. In the fifth O site, O(5) is bonded in a bent 120 degrees geometry to three equivalent Rb(1), one B(1), and one B(2) atom.