DOE OSTI2020
Fe14Cu7(PO4)18 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are seven inequivalent Fe sites. In the first Fe site, Fe is bonded to six O atoms to form FeO6 octahedra that share a cornercorner with one FeO6 octahedra, corners with six PO4 tetrahedra, an edgeedge with one FeO6 octahedra, and an edgeedge with one CuO5 square pyramid. The corner-sharing octahedral tilt angles are 65°. There are a spread of Fe–O bond distances ranging from 1.89–2.17 Å. In the second Fe site, Fe is bonded to six O atoms to form FeO6 octahedra that share a cornercorner with one FeO6 octahedra, corners with six PO4 tetrahedra, an edgeedge with one FeO6 octahedra, and an edgeedge with one CuO5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 65°. There are a spread of Fe–O bond distances ranging from 1.89–2.16 Å. In the third Fe site, Fe is bonded to six O atoms to form FeO6 octahedra that share a cornercorner with one CuO6 octahedra, corners with six PO4 tetrahedra, an edgeedge with one FeO6 octahedra, and an edgeedge with one CuO5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 65°. There are a spread of Fe–O bond distances ranging from 1.89–2.16 Å. In the fourth Fe site, Fe is bonded to six O atoms to form FeO6 octahedra that share corners with six PO4 tetrahedra, an edgeedge with one FeO6 octahedra, and an edgeedge with one CuO5 square pyramid. There are a spread of Fe–O bond distances ranging from 1.91–2.19 Å. In the fifth Fe site, Fe is bonded to six O atoms to form FeO6 octahedra that share corners with six PO4 tetrahedra, an edgeedge with one FeO6 octahedra, and an edgeedge with one CuO5 trigonal bipyramid. There are a spread of Fe–O bond distances ranging from 1.91–2.19 Å. In the sixth Fe site, Fe is bonded to six O atoms to form FeO6 octahedra that share corners with six PO4 tetrahedra, an edgeedge with one FeO6 octahedra, and an edgeedge with one CuO5 trigonal bipyramid. There are a spread of Fe–O bond distances ranging from 1.91–2.22 Å. In the seventh Fe site, Fe is bonded to six O atoms to form FeO6 octahedra that share corners with two FeO6 octahedra, corners with six PO4 tetrahedra, and corners with two CuO5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 65°. There are a spread of Fe–O bond distances ranging from 2.03–2.34 Å. There are four inequivalent Cu sites. In the first Cu site, Cu is bonded to five O atoms to form distorted CuO5 square pyramids that share a cornercorner with one CuO6 octahedra, corners with five PO4 tetrahedra, and edges with two FeO6 octahedra. The corner-sharing octahedral tilt angles are 70°. There are a spread of Cu–O bond distances ranging from 1.92–2.30 Å. In the second Cu site, Cu is bonded to five O atoms to form distorted CuO5 trigonal bipyramids that share a cornercorner with one FeO6 octahedra, corners with five PO4 tetrahedra, and edges with two FeO6 octahedra. The corner-sharing octahedral tilt angles are 69°. There are a spread of Cu–O bond distances ranging from 1.94–2.29 Å. In the third Cu site, Cu is bonded to five O atoms to form distorted CuO5 trigonal bipyramids that share a cornercorner with one FeO6 octahedra, corners with five PO4 tetrahedra, and edges with two FeO6 octahedra. The corner-sharing octahedral tilt angles are 69°. There are a spread of Cu–O bond distances ranging from 1.95–2.28 Å. In the fourth Cu site, Cu is bonded to six O atoms to form CuO6 octahedra that share corners with two equivalent FeO6 octahedra, corners with two equivalent CuO5 square pyramids, and corners with six PO4 tetrahedra. The corner-sharing octahedral tilt angles are 65°. There are a spread of Cu–O bond distances ranging from 1.99–2.38 Å. There are nine inequivalent P sites. In the first P site, P is bonded to four O atoms to form PO4 tetrahedra that share corners with six FeO6 octahedra and a cornercorner with one CuO5 square pyramid. The corner-sharing octahedra tilt angles range from 25–55°. There are a spread of P–O bond distances ranging from 1.51–1.58 Å. In the second P site, P is bonded to four O atoms to form PO4 tetrahedra that share a cornercorner with one CuO6 octahedra, corners with five FeO6 octahedra, and a cornercorner with one CuO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 26–55°. There are a spread of P–O bond distances ranging from 1.51–1.58 Å. In the third P site, P is bonded to four O atoms to form PO4 tetrahedra that share corners with six FeO6 octahedra and a cornercorner with one CuO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 25–55°. There are a spread of P–O bond distances ranging from 1.51–1.57 Å. In the fourth P site, P is bonded to four O atoms to form PO4 tetrahedra that share corners with four FeO6 octahedra and corners with two equivalent CuO5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 22–60°. There are a spread of P–O bond distances ranging from 1.53–1.57 Å. In the fifth P site, P is bonded to four O atoms to form PO4 tetrahedra that share corners with four FeO6 octahedra, a cornercorner with one CuO5 square pyramid, and a cornercorner with one CuO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 22–60°. There are a spread of P–O bond distances ranging from 1.53–1.57 Å. In the sixth P site, P is bonded to four O atoms to form PO4 tetrahedra that share a cornercorner with one CuO6 octahedra, corners with three FeO6 octahedra, a cornercorner with one CuO5 square pyramid, and a cornercorner with one CuO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 22–62°. There are a spread of P–O bond distances ranging from 1.53–1.56 Å. In the seventh P site, P is bonded to four O atoms to form PO4 tetrahedra that share a cornercorner with one CuO6 octahedra, corners with four FeO6 octahedra, a cornercorner with one CuO5 square pyramid, and a cornercorner with one CuO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 32–61°. There are a spread of P–O bond distances ranging from 1.51–1.58 Å. In the eighth P site, P is bonded to four O atoms to form PO4 tetrahedra that share corners with five FeO6 octahedra, a cornercorner with one CuO5 square pyramid, and a cornercorner with one CuO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 32–61°. There are a spread of P–O bond distances ranging from 1.51–1.58 Å. In the ninth P site, P is bonded to four O atoms to form PO4 tetrahedra that share corners with five FeO6 octahedra and corners with two CuO5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 33–61°. There are a spread of P–O bond distances ranging from 1.51–1.58 Å. There are thirty-six inequivalent O sites. In the first O site, O is bonded in a 3-coordinate geometry to two Fe and one P atom. In the second O site, O is bonded in a 3-coordinate geometry to two equivalent Fe and one P atom. In the third O site, O is bonded in a 3-coordinate geometry to two Fe and one P atom. In the fourth O site, O is bonded in a bent 150 degrees geometry to one Fe and one P atom. In the fifth O site, O is bonded in a bent 150 degrees geometry to one Cu and one P atom. In the sixth O site, O is bonded in a bent 150 degrees geometry to one Fe and one P atom. In the seventh O site, O is bonded in a distorted trigonal planar geometry to one Fe, one Cu, and one P atom. In the eighth O site, O is bonded in a distorted trigonal planar geometry to one Fe, one Cu, and one P atom. In the ninth O site, O is bonded in a distorted trigonal planar geometry to one Fe, one Cu, and one P atom. In the tenth O site, O is bonded in a bent 150 degrees geometry to one Fe and one P atom. In the eleventh O site, O is bonded in a bent 150 degrees geometry to one Fe and one P atom. In the twelfth O site, O is bonded in a bent 150 degrees geometry to one Fe and one P atom. In the thirteenth O site, O is bonded in a bent 150 degrees geometry to one Fe and one P atom. In the fourteenth O site, O is bonded in a bent 150 degrees geometry to one Fe and one P atom. In the fifteenth O site, O is bonded in a bent 150 degrees geometry to one Fe and one P atom. In the sixteenth O site, O is bonded in a distorted trigonal planar geometry to one Fe, one Cu, and one P atom. In the seventeenth O site, O is bonded in a distorted trigonal planar geometry to one Fe, one Cu, and one P atom. In the eighteenth O site, O is bonded in a distorted trigonal planar geometry to two Cu and one P atom. In the nineteenth O site, O is bonded in a 3-coordinate geometry to one Fe, one Cu, and one P atom. In the twentieth O site, O is bonded in a 3-coordinate geometry to one Fe, one Cu, and one P atom. In the twenty-first O site, O is bonded in a 3-coordinate geometry to one Fe, one Cu, and one P atom. In the twenty-second O site, O is bonded in a distorted trigonal planar geometry to one Fe, one Cu, and one P atom. In the twenty-third O site, O is bonded in a distorted trigonal planar geometry to one Fe, one Cu, and one P atom. In the twenty-fourth O site, O is bonded in a distorted trigonal planar geometry to one Fe, one Cu, and one P atom. In the twenty-fifth O site, O is bonded in a bent 150 degrees geometry to one Fe and one P atom. In the twenty-sixth O site, O is bonded in a bent 150 degrees geometry to one Fe and one P atom. In the twenty-seventh O site, O is bonded in a bent 150 degrees geometry to one Fe and one P atom. In the twenty-eighth O site, O is bonded in a distorted trigonal planar geometry to one Fe, one Cu, and one P atom. In the twenty-ninth O site, O is bonded in a distorted trigonal planar geometry to one Fe, one Cu, and one P atom. In the thirtieth O site, O is bonded in a distorted trigonal planar geometry to one Fe, one Cu, and one P atom. In the thirty-first O site, O is bonded in a trigonal planar geometry to one Fe, one Cu, and one P atom. In the thirty-second O site, O is bonded in a trigonal planar geometry to two Fe and one P atom. In the thirty-third O site, O is bonded in a trigonal planar geometry to two Fe and one P atom. In the thirty-fourth O site, O is bonded in a distorted trigonal planar geometry to two equivalent Fe and one P atom. In the thirty-fifth O site, O is bonded in a distorted trigonal planar geometry to two Fe and one P atom. In the thirty-sixth O site, O is bonded in a distorted trigonal planar geometry to two Fe and one P atom.