Materials Data on KFe3P8(H11O18)2 by Materials Project
KFe3P8(H7O16)2(H2O)4 crystallizes in the monoclinic C2/c space group. The structure is two-dimensional and consists of sixteen water molecules and two KFe3P8(H7O16)2 sheets oriented in the (0, 0, 1) direction. In each KFe3P8(H7O16)2 sheet, K1+ is bonded in a 12-coordinate geometry to twelve O2- atoms. There are a spread of K–O bond distances ranging from 2.92–3.16 Å. There are two inequivalent Fe3+ sites. In the first Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with six PO4 tetrahedra. There are a spread of Fe–O bond distances ranging from 1.98–2.10 Å. In the second Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with six PO4 tetrahedra. There are a spread of Fe–O bond distances ranging from 1.98–2.08 Å. There are four inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two FeO6 octahedra. The corner-sharing octahedra tilt angles range from 25–41°. There are a spread of P–O bond distances ranging from 1.51–1.59 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two equivalent FeO6 octahedra. The corner-sharing octahedra tilt angles range from 28–40°. There are a spread of P–O bond distances ranging from 1.52–1.60 Å. In the third P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two FeO6 octahedra. The corner-sharing octahedra tilt angles range from 18–44°. There are a spread of P–O bond distances ranging from 1.51–1.59 Å. In the fourth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three FeO6 octahedra. The corner-sharing octahedra tilt angles range from 39–47°. There is three shorter (1.54 Å) and one longer (1.61 Å) P–O bond length. There are seven inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.01 Å. In the second H1+ site, H1+ is bonded in a distorted linear geometry to two O2- atoms. There is one shorter (1.01 Å) and one longer (1.66 Å) H–O bond length. In the third H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.00 Å. In the fourth H1+ site, H1+ is bonded in a linear geometry to two O2- atoms. There is one shorter (1.02 Å) and one longer (1.61 Å) H–O bond length. In the fifth H1+ site, H1+ is bonded in a distorted single-bond geometry to one O2- atom. The H–O bond length is 1.01 Å. In the sixth H1+ site, H1+ is bonded in a distorted linear geometry to two O2- atoms. There is one shorter (1.01 Å) and one longer (1.66 Å) H–O bond length. In the seventh H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.00 Å. There are sixteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 150 degrees geometry to one Fe3+ and one P5+ atom. In the second O2- site, O2- is bonded in a 2-coordinate geometry to one K1+, one Fe3+, and one P5+ atom. In the third O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one K1+, one P5+, and one H1+ atom. In the fourth O2- site, O2- is bonded in a bent 120 degrees geometry to one P5+ and one H1+ atom. In the fifth O2- site, O2- is bonded in a bent 150 degrees geometry to one Fe3+ and one P5+ atom. In the sixth O2- site, O2- is bonded in a 2-coordinate geometry to one K1+, one Fe3+, and one P5+ atom. In the seventh O2- site, O2- is bonded in a bent 120 degrees geometry to one P5+ and one H1+ atom. In the eighth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one K1+, one P5+, and one H1+ atom. In the ninth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Fe3+ and one P5+ atom. In the tenth O2- site, O2- is bonded in a 2-coordinate geometry to one K1+, one Fe3+, and one P5+ atom. In the eleventh O2- site, O2- is bonded in a bent 120 degrees geometry to one P5+ and one H1+ atom. In the twelfth O2- site, O2- is bonded in a bent 120 degrees geometry to one K1+, one P5+, and one H1+ atom. In the thirteenth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Fe3+, one P5+, and one H1+ atom. In the fourteenth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Fe3+, one P5+, and one H1+ atom. In the fifteenth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Fe3+, one P5+, and one H1+ atom. In the sixteenth O2- site, O2- is bonded in a bent 120 degrees geometry to one P5+ and one H1+ atom.