Mn5P3O12Cl crystallizes in the hexagonal P6_3/m space group. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded in a 6-coordinate geometry to three equivalent O(2) and three equivalent O(3) atoms. In the second Mn site, Mn(2) is bonded to one O(2), four equivalent O(1), and one Cl(1) atom to form distorted MnClO5 pentagonal pyramids that share corners with six equivalent Mn(2)ClO5 pentagonal pyramids, corners with three equivalent P(1)O4 tetrahedra, and  an edgeedge with one P(1)O4 tetrahedra. P(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form PO4 tetrahedra that share corners with three equivalent Mn(2)ClO5 pentagonal pyramids and  an edgeedge with one Mn(2)ClO5 pentagonal pyramid. There are three inequivalent O sites. In the first O site, O(3) is bonded in a 3-coordinate geometry to two equivalent Mn(1) and one P(1) atom. In the second O site, O(1) is bonded in a 3-coordinate geometry to two equivalent Mn(2) and one P(1) atom. In the third O site, O(2) is bonded to one Mn(2), two equivalent Mn(1), and one P(1) atom to form distorted edge-sharing OMn3P tetrahedra. Cl(1) is bonded in a trigonal planar geometry to three equivalent Mn(2) atoms.
Mn5P3O12Cl crystallizes in the hexagonal P6_3/m space group. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded in a 6-coordinate geometry to three equivalent O(2) and three equivalent O(3) atoms. All Mn(1)-O(2) bond lengths are 2.31 Å. All Mn(1)-O(3) bond lengths are 2.25 Å. In the second Mn site, Mn(2) is bonded to one O(2), four equivalent O(1), and one Cl(1) atom to form distorted MnClO5 pentagonal pyramids that share corners with six equivalent Mn(2)ClO5 pentagonal pyramids, corners with three equivalent P(1)O4 tetrahedra, and  an edgeedge with one P(1)O4 tetrahedra. The Mn(2)-O(2) bond length is 2.23 Å. There are two shorter (2.16 Å) and two longer (2.37 Å) Mn(2)-O(1) bond lengths. The Mn(2)-Cl(1) bond length is 2.53 Å. P(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form PO4 tetrahedra that share corners with three equivalent Mn(2)ClO5 pentagonal pyramids and  an edgeedge with one Mn(2)ClO5 pentagonal pyramid. The P(1)-O(2) bond length is 1.59 Å. The P(1)-O(3) bond length is 1.54 Å. Both P(1)-O(1) bond lengths are 1.55 Å. There are three inequivalent O sites. In the first O site, O(3) is bonded in a 3-coordinate geometry to two equivalent Mn(1) and one P(1) atom. In the second O site, O(1) is bonded in a 3-coordinate geometry to two equivalent Mn(2) and one P(1) atom. In the third O site, O(2) is bonded to one Mn(2), two equivalent Mn(1), and one P(1) atom to form distorted edge-sharing OMn3P tetrahedra. Cl(1) is bonded in a trigonal planar geometry to three equivalent Mn(2) atoms.