Rb3PO4 crystallizes in the orthorhombic Pnma space group. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a 6-coordinate geometry to one O(2), one O(3), and four equivalent O(1) atoms. In the second Rb site, Rb(2) is bonded in a 7-coordinate geometry to two equivalent O(2), two equivalent O(3), and three equivalent O(1) atoms. P(1) is bonded in a tetrahedral geometry to one O(2), one O(3), and two equivalent O(1) atoms. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to two equivalent Rb(1), three equivalent Rb(2), and one P(1) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to one Rb(1), four equivalent Rb(2), and one P(1) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one Rb(1), four equivalent Rb(2), and one P(1) atom.
Rb3PO4 crystallizes in the orthorhombic Pnma space group. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a 6-coordinate geometry to one O(2), one O(3), and four equivalent O(1) atoms. The Rb(1)-O(2) bond length is 2.73 Å. The Rb(1)-O(3) bond length is 2.78 Å. There are two shorter (2.97 Å) and two longer (3.00 Å) Rb(1)-O(1) bond lengths. In the second Rb site, Rb(2) is bonded in a 7-coordinate geometry to two equivalent O(2), two equivalent O(3), and three equivalent O(1) atoms. There is one shorter (2.88 Å) and one longer (2.95 Å) Rb(2)-O(2) bond length. There is one shorter (2.86 Å) and one longer (3.07 Å) Rb(2)-O(3) bond length. There are a spread of Rb(2)-O(1) bond distances ranging from 2.92-3.23 Å. P(1) is bonded in a tetrahedral geometry to one O(2), one O(3), and two equivalent O(1) atoms. The P(1)-O(2) bond length is 1.55 Å. The P(1)-O(3) bond length is 1.55 Å. Both P(1)-O(1) bond lengths are 1.55 Å. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to two equivalent Rb(1), three equivalent Rb(2), and one P(1) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to one Rb(1), four equivalent Rb(2), and one P(1) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one Rb(1), four equivalent Rb(2), and one P(1) atom.