FeZn2P2(H2O3)4 crystallizes in the monoclinic P2_1/c space group. Fe(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form FeO6 octahedra that share corners with two equivalent P(1)O4 tetrahedra. Zn(1) is bonded to one O(4), one O(5), and two equivalent O(6) atoms to form ZnO4 tetrahedra that share corners with two equivalent Zn(1)O4 tetrahedra and corners with four equivalent P(1)O4 tetrahedra. P(1) is bonded to one O(3), one O(4), one O(5), and one O(6) atom to form PO4 tetrahedra that share  a cornercorner with one Fe(1)O6 octahedra and corners with four equivalent Zn(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 50°. There are four inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one O(1) atom. In the second H site, H(2) is bonded in a single-bond geometry to one O(1) and one O(3) atom. In the third H site, H(3) is bonded in a distorted single-bond geometry to one O(2) and one O(5) atom. In the fourth H site, H(4) is bonded in a single-bond geometry to one O(2) atom. There are six inequivalent O sites. In the first O site, O(3) is bonded in a 3-coordinate geometry to one Fe(1), one P(1), and one H(2) atom. In the second O site, O(4) is bonded in a distorted bent 150 degrees geometry to one Zn(1) and one P(1) atom. In the third O site, O(5) is bonded in a distorted trigonal planar geometry to one Zn(1), one P(1), and one H(3) atom. In the fourth O site, O(6) is bonded in a trigonal planar geometry to two equivalent Zn(1) and one P(1) atom. In the fifth O site, O(1) is bonded in a distorted water-like geometry to one Fe(1), one H(1), and one H(2) atom. In the sixth O site, O(2) is bonded in a distorted water-like geometry to one Fe(1), one H(3), and one H(4) atom.
FeZn2P2(H2O3)4 crystallizes in the monoclinic P2_1/c space group. Fe(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form FeO6 octahedra that share corners with two equivalent P(1)O4 tetrahedra. Both Fe(1)-O(1) bond lengths are 2.14 Å. Both Fe(1)-O(2) bond lengths are 2.14 Å. Both Fe(1)-O(3) bond lengths are 2.22 Å. Zn(1) is bonded to one O(4), one O(5), and two equivalent O(6) atoms to form ZnO4 tetrahedra that share corners with two equivalent Zn(1)O4 tetrahedra and corners with four equivalent P(1)O4 tetrahedra. The Zn(1)-O(4) bond length is 1.92 Å. The Zn(1)-O(5) bond length is 1.97 Å. There is one shorter (2.02 Å) and one longer (2.03 Å) Zn(1)-O(6) bond length. P(1) is bonded to one O(3), one O(4), one O(5), and one O(6) atom to form PO4 tetrahedra that share  a cornercorner with one Fe(1)O6 octahedra and corners with four equivalent Zn(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 50°. The P(1)-O(3) bond length is 1.55 Å. The P(1)-O(4) bond length is 1.53 Å. The P(1)-O(5) bond length is 1.56 Å. The P(1)-O(6) bond length is 1.59 Å. There are four inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one O(1) atom. The H(1)-O(1) bond length is 0.99 Å. In the second H site, H(2) is bonded in a single-bond geometry to one O(1) and one O(3) atom. The H(2)-O(1) bond length is 1.00 Å. The H(2)-O(3) bond length is 1.74 Å. In the third H site, H(3) is bonded in a distorted single-bond geometry to one O(2) and one O(5) atom. The H(3)-O(2) bond length is 1.00 Å. The H(3)-O(5) bond length is 1.70 Å. In the fourth H site, H(4) is bonded in a single-bond geometry to one O(2) atom. The H(4)-O(2) bond length is 0.98 Å. There are six inequivalent O sites. In the first O site, O(3) is bonded in a 3-coordinate geometry to one Fe(1), one P(1), and one H(2) atom. In the second O site, O(4) is bonded in a distorted bent 150 degrees geometry to one Zn(1) and one P(1) atom. In the third O site, O(5) is bonded in a distorted trigonal planar geometry to one Zn(1), one P(1), and one H(3) atom. In the fourth O site, O(6) is bonded in a trigonal planar geometry to two equivalent Zn(1) and one P(1) atom. In the fifth O site, O(1) is bonded in a distorted water-like geometry to one Fe(1), one H(1), and one H(2) atom. In the sixth O site, O(2) is bonded in a distorted water-like geometry to one Fe(1), one H(3), and one H(4) atom.