RuP3O9 crystallizes in the monoclinic C2/c space group. Ru(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form RuO6 octahedra that share corners with two equivalent P(2)O4 tetrahedra and corners with four equivalent P(1)O4 tetrahedra. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(2), one O(3), one O(4), and one O(5) atom to form PO4 tetrahedra that share corners with two equivalent Ru(1)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra, and  a cornercorner with one P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 38-44°. In the second P site, P(2) is bonded to two equivalent O(1) and two equivalent O(4) atoms to form PO4 tetrahedra that share corners with two equivalent Ru(1)O6 octahedra and corners with two equivalent P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 36°. There are five inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one Ru(1) and one P(2) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Ru(1) and one P(1) atom. In the third O site, O(3) is bonded in a distorted bent 150 degrees geometry to one Ru(1) and one P(1) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one P(1) and one P(2) atom. In the fifth O site, O(5) is bonded in a linear geometry to two equivalent P(1) atoms.
RuP3O9 crystallizes in the monoclinic C2/c space group. Ru(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form RuO6 octahedra that share corners with two equivalent P(2)O4 tetrahedra and corners with four equivalent P(1)O4 tetrahedra. Both Ru(1)-O(1) bond lengths are 2.04 Å. Both Ru(1)-O(2) bond lengths are 2.04 Å. Both Ru(1)-O(3) bond lengths are 2.07 Å. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(2), one O(3), one O(4), and one O(5) atom to form PO4 tetrahedra that share corners with two equivalent Ru(1)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra, and  a cornercorner with one P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 38-44°. The P(1)-O(2) bond length is 1.51 Å. The P(1)-O(3) bond length is 1.50 Å. The P(1)-O(4) bond length is 1.59 Å. The P(1)-O(5) bond length is 1.58 Å. In the second P site, P(2) is bonded to two equivalent O(1) and two equivalent O(4) atoms to form PO4 tetrahedra that share corners with two equivalent Ru(1)O6 octahedra and corners with two equivalent P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 36°. Both P(2)-O(1) bond lengths are 1.50 Å. Both P(2)-O(4) bond lengths are 1.59 Å. There are five inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one Ru(1) and one P(2) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Ru(1) and one P(1) atom. In the third O site, O(3) is bonded in a distorted bent 150 degrees geometry to one Ru(1) and one P(1) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one P(1) and one P(2) atom. In the fifth O site, O(5) is bonded in a linear geometry to two equivalent P(1) atoms.