BaMo2P4O16 crystallizes in the monoclinic P2_1/c space group. Ba(1) is bonded in a 10-coordinate geometry to two equivalent O(1), two equivalent O(2), two equivalent O(3), two equivalent O(4), and two equivalent O(8) atoms. Mo(1) is bonded to one O(2), one O(3), one O(4), one O(6), one O(7), and one O(8) atom to form distorted MoO6 octahedra that share corners with two equivalent P(2)O4 tetrahedra and corners with three 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(5), and one O(7) atom to form PO4 tetrahedra that share corners with three equivalent Mo(1)O6 octahedra and  a cornercorner with one P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 35-51°. In the second P site, P(2) is bonded to one O(1), one O(4), one O(5), and one O(8) atom to form PO4 tetrahedra that share corners with two equivalent Mo(1)O6 octahedra and  a cornercorner with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 41-42°. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one Ba(1) and one P(2) atom. In the second O site, O(2) is bonded in a 1-coordinate geometry to one Ba(1), one Mo(1), and one P(1) atom. In the third O site, O(3) is bonded in a 2-coordinate geometry to one Ba(1), one Mo(1), and one P(1) atom. In the fourth O site, O(4) is bonded in a 2-coordinate geometry to one Ba(1), one Mo(1), and one P(2) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one P(1) and one P(2) atom. In the sixth O site, O(6) is bonded in a single-bond geometry to one Mo(1) atom. In the seventh O site, O(7) is bonded in a bent 150 degrees geometry to one Mo(1) and one P(1) atom. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to one Ba(1), one Mo(1), and one P(2) atom.
BaMo2P4O16 crystallizes in the monoclinic P2_1/c space group. Ba(1) is bonded in a 10-coordinate geometry to two equivalent O(1), two equivalent O(2), two equivalent O(3), two equivalent O(4), and two equivalent O(8) atoms. Both Ba(1)-O(1) bond lengths are 2.67 Å. Both Ba(1)-O(2) bond lengths are 3.14 Å. Both Ba(1)-O(3) bond lengths are 3.23 Å. Both Ba(1)-O(4) bond lengths are 3.16 Å. Both Ba(1)-O(8) bond lengths are 2.79 Å. Mo(1) is bonded to one O(2), one O(3), one O(4), one O(6), one O(7), and one O(8) atom to form distorted MoO6 octahedra that share corners with two equivalent P(2)O4 tetrahedra and corners with three equivalent P(1)O4 tetrahedra. The Mo(1)-O(2) bond length is 2.21 Å. The Mo(1)-O(3) bond length is 2.13 Å. The Mo(1)-O(4) bond length is 2.06 Å. The Mo(1)-O(6) bond length is 1.70 Å. The Mo(1)-O(7) bond length is 2.04 Å. The Mo(1)-O(8) bond length is 2.06 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(5), and one O(7) atom to form PO4 tetrahedra that share corners with three equivalent Mo(1)O6 octahedra and  a cornercorner with one P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 35-51°. The P(1)-O(2) bond length is 1.53 Å. The P(1)-O(3) bond length is 1.54 Å. The P(1)-O(5) bond length is 1.60 Å. The P(1)-O(7) bond length is 1.53 Å. In the second P site, P(2) is bonded to one O(1), one O(4), one O(5), and one O(8) atom to form PO4 tetrahedra that share corners with two equivalent Mo(1)O6 octahedra and  a cornercorner with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 41-42°. The P(2)-O(1) bond length is 1.48 Å. The P(2)-O(4) bond length is 1.56 Å. The P(2)-O(5) bond length is 1.62 Å. The P(2)-O(8) bond length is 1.56 Å. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one Ba(1) and one P(2) atom. In the second O site, O(2) is bonded in a 1-coordinate geometry to one Ba(1), one Mo(1), and one P(1) atom. In the third O site, O(3) is bonded in a 2-coordinate geometry to one Ba(1), one Mo(1), and one P(1) atom. In the fourth O site, O(4) is bonded in a 2-coordinate geometry to one Ba(1), one Mo(1), and one P(2) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one P(1) and one P(2) atom. In the sixth O site, O(6) is bonded in a single-bond geometry to one Mo(1) atom. In the seventh O site, O(7) is bonded in a bent 150 degrees geometry to one Mo(1) and one P(1) atom. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to one Ba(1), one Mo(1), and one P(2) atom.