FeP2(H4O5)2 crystallizes in the monoclinic P2_1/c space group. Fe(1) is bonded in a distorted square co-planar geometry to two equivalent O(1) and two equivalent O(3) atoms. P(1) is bonded in a tetrahedral geometry to one O(1), one O(2), one O(4), and one O(5) atom. There are four inequivalent H sites. In the first H site, H(1) is bonded in a distorted linear geometry to one O(3) and one O(5) atom. In the second H site, H(2) is bonded in a bent 150 degrees geometry to one O(2) and one O(3) atom. In the third H site, H(3) is bonded in a linear geometry to one O(1) and one O(4) atom. In the fourth H site, H(4) is bonded in a single-bond geometry to one O(3) atom. There are five inequivalent O sites. In the first O site, O(4) is bonded in a bent 120 degrees geometry to one P(1) and one H(3) atom. In the second O site, O(5) is bonded in a bent 120 degrees geometry to one P(1) and one H(1) atom. In the third O site, O(1) is bonded in a distorted trigonal planar geometry to one Fe(1), one P(1), and one H(3) atom. In the fourth O site, O(2) is bonded in a bent 120 degrees geometry to one P(1) and one H(2) atom. In the fifth O site, O(3) is bonded in a 4-coordinate geometry to one Fe(1), one H(1), one H(2), and one H(4) atom.
FeP2(H4O5)2 crystallizes in the monoclinic P2_1/c space group. Fe(1) is bonded in a distorted square co-planar geometry to two equivalent O(1) and two equivalent O(3) atoms. Both Fe(1)-O(1) bond lengths are 2.30 Å. Both Fe(1)-O(3) bond lengths are 2.03 Å. P(1) is bonded in a tetrahedral geometry to one O(1), one O(2), one O(4), and one O(5) atom. The P(1)-O(1) bond length is 1.52 Å. The P(1)-O(2) bond length is 1.57 Å. The P(1)-O(4) bond length is 1.58 Å. The P(1)-O(5) bond length is 1.56 Å. There are four inequivalent H sites. In the first H site, H(1) is bonded in a distorted linear geometry to one O(3) and one O(5) atom. The H(1)-O(3) bond length is 1.54 Å. The H(1)-O(5) bond length is 1.04 Å. In the second H site, H(2) is bonded in a bent 150 degrees geometry to one O(2) and one O(3) atom. The H(2)-O(2) bond length is 1.11 Å. The H(2)-O(3) bond length is 1.37 Å. In the third H site, H(3) is bonded in a linear geometry to one O(1) and one O(4) atom. The H(3)-O(1) bond length is 1.56 Å. The H(3)-O(4) bond length is 1.03 Å. In the fourth H site, H(4) is bonded in a single-bond geometry to one O(3) atom. The H(4)-O(3) bond length is 0.99 Å. There are five inequivalent O sites. In the first O site, O(4) is bonded in a bent 120 degrees geometry to one P(1) and one H(3) atom. In the second O site, O(5) is bonded in a bent 120 degrees geometry to one P(1) and one H(1) atom. In the third O site, O(1) is bonded in a distorted trigonal planar geometry to one Fe(1), one P(1), and one H(3) atom. In the fourth O site, O(2) is bonded in a bent 120 degrees geometry to one P(1) and one H(2) atom. In the fifth O site, O(3) is bonded in a 4-coordinate geometry to one Fe(1), one H(1), one H(2), and one H(4) atom.