DOE OSTI2020
Na6Fe3(PO4)4 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are twelve inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Na–O bond distances ranging from 2.36–2.73 Å. In the second Na1+ site, Na1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Na–O bond distances ranging from 2.30–2.81 Å. In the third Na1+ site, Na1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Na–O bond distances ranging from 2.33–2.60 Å. In the fourth Na1+ site, Na1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Na–O bond distances ranging from 2.28–2.79 Å. In the fifth Na1+ site, Na1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Na–O bond distances ranging from 2.29–2.78 Å. In the sixth Na1+ site, Na1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Na–O bond distances ranging from 2.28–2.63 Å. In the seventh Na1+ site, Na1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Na–O bond distances ranging from 2.32–2.64 Å. In the eighth Na1+ site, Na1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Na–O bond distances ranging from 2.30–2.77 Å. In the ninth Na1+ site, Na1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Na–O bond distances ranging from 2.37–2.70 Å. In the tenth Na1+ site, Na1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Na–O bond distances ranging from 2.36–2.72 Å. In the eleventh Na1+ site, Na1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Na–O bond distances ranging from 2.36–2.71 Å. In the twelfth Na1+ site, Na1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Na–O bond distances ranging from 2.28–2.63 Å. There are six inequivalent Fe2+ sites. In the first Fe2+ site, Fe2+ is bonded to six O2- atoms to form distorted FeO6 octahedra that share corners with four PO4 tetrahedra, corners with two FeO5 trigonal bipyramids, and an edgeedge with one PO4 tetrahedra. There are a spread of Fe–O bond distances ranging from 2.03–2.43 Å. In the second Fe2+ site, Fe2+ is bonded to six O2- atoms to form distorted FeO6 octahedra that share corners with four PO4 tetrahedra, corners with two FeO5 trigonal bipyramids, and an edgeedge with one PO4 tetrahedra. There are a spread of Fe–O bond distances ranging from 2.03–2.43 Å. In the third Fe2+ site, Fe2+ is bonded to five O2- atoms to form FeO5 trigonal bipyramids that share corners with two FeO6 octahedra, corners with five PO4 tetrahedra, and corners with two FeO5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 73–77°. There are a spread of Fe–O bond distances ranging from 2.09–2.12 Å. In the fourth Fe2+ site, Fe2+ is bonded to five O2- atoms to form distorted FeO5 trigonal bipyramids that share corners with three PO4 tetrahedra, corners with two FeO5 trigonal bipyramids, and an edgeedge with one PO4 tetrahedra. There are a spread of Fe–O bond distances ranging from 2.06–2.30 Å. In the fifth Fe2+ site, Fe2+ is bonded to five O2- atoms to form distorted FeO5 trigonal bipyramids that share corners with three PO4 tetrahedra, corners with two FeO5 trigonal bipyramids, and an edgeedge with one PO4 tetrahedra. There are a spread of Fe–O bond distances ranging from 2.06–2.30 Å. In the sixth Fe2+ site, Fe2+ is bonded to five O2- atoms to form FeO5 trigonal bipyramids that share corners with two FeO6 octahedra, corners with five PO4 tetrahedra, and corners with two FeO5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 73–76°. There are a spread of Fe–O bond distances ranging from 2.08–2.12 Å. There are eight 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 and a cornercorner with one FeO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 49–62°. There is three shorter (1.56 Å) and one longer (1.57 Å) P–O bond length. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with four FeO5 trigonal bipyramids and an edgeedge with one FeO6 octahedra. There is three shorter (1.56 Å) and one longer (1.57 Å) P–O bond length. In the third P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with four FeO5 trigonal bipyramids and an edgeedge with one FeO6 octahedra. There is three shorter (1.56 Å) and one longer (1.57 Å) P–O bond length. In the fourth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two FeO6 octahedra and a cornercorner with one FeO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 49–63°. There is three shorter (1.56 Å) and one longer (1.57 Å) P–O bond length. In the fifth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one FeO5 trigonal bipyramid. There are a spread of P–O bond distances ranging from 1.54–1.59 Å. In the sixth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two equivalent FeO6 octahedra, corners with two FeO5 trigonal bipyramids, and an edgeedge with one FeO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 37–45°. There are a spread of P–O bond distances ranging from 1.53–1.58 Å. In the seventh P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two equivalent FeO6 octahedra, corners with two FeO5 trigonal bipyramids, and an edgeedge with one FeO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 37–45°. There are a spread of P–O bond distances ranging from 1.53–1.58 Å. In the eighth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one FeO5 trigonal bipyramid. There are a spread of P–O bond distances ranging from 1.54–1.59 Å. There are thirty-two inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Fe2+, and one P5+ atom. In the second O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Fe2+, and one P5+ atom. In the third O2- site, O2- is bonded in a 1-coordinate geometry to two Na1+, one Fe2+, and one P5+ atom. In the fourth O2- site, O2- is bonded in a 1-coordinate geometry to two Na1+, one Fe2+, and one P5+ atom. In the fifth O2- site, O2- is bonded in a 1-coordinate geometry to three Na1+, one Fe2+, and one P5+ atom. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to one Na1+, two Fe2+, and one P5+ atom. In the seventh O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one Fe2+, and one P5+ atom. In the eighth O2- site, O2- is bonded in a distorted tetrahedral geometry to one Na1+, two Fe2+, and one P5+ atom. In the ninth O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one Fe2+, and one P5+ atom. In the tenth O2- site, O2- is bonded in a distorted tetrahedral geometry to one Na1+, two Fe2+, and one P5+ atom. In the eleventh O2- site, O2- is bonded in a 4-coordinate geometry to one Na1+, two Fe2+, and one P5+ atom. In the twelfth O2- site, O2- is bonded in a 1-coordinate geometry to three Na1+, one Fe2+, and one P5+ atom. In the thirteenth O2- site, O2- is bonded in a 1-coordinate geometry to two Na1+, one Fe2+, and one P5+ atom. In the fourteenth O2- site, O2- is bonded in a 1-coordinate geometry to two Na1+ and one P5+ atom. In the fifteenth O2- site, O2- is bonded in a 1-coordinate geometry to five Na1+ and one P5+ atom. In the sixteenth O2- site, O2- is bonded in a 1-coordinate geometry to four Na1+ and one P5+ atom. In the seventeenth O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one Fe2+, and one P5+ atom. In the eighteenth O2- site, O2- is bonded in a 1-coordinate geometry to two Na1+, one Fe2+, and one P5+ atom. In the nineteenth O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Fe2+, and one P5+ atom. In the twentieth O2- site, O2- is bonded in a 1-coordinate geometry to four Na1+ and one P5+ atom. In the twenty-first O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Fe2+, and one P5+ atom. In the twenty-second O2- site, O2- is bonded in a 4-coordinate geometry to one Na1+, two Fe2+, and one P5+ atom. In the twenty-third O2- site, O2- is bonded in a 4-coordinate geometry to one Na1+, two Fe2+, and one P5+ atom. In the twenty-fourth O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one Fe2+, and one P5+ atom. In the twenty-fifth O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one Fe2+, and one P5+ atom. In the twenty-sixth O2- site, O2- is bonded in a 4-coordinate geometry to one Na1+, two Fe2+, and one P5+ atom. In the twenty-seventh O2- site, O2- is bonded in a 4-coordinate geometry to one Na1+, two Fe2+, and one P5+ atom. In the twenty-eighth O2- site, O2- is bonded in a 1-coordinate geometry to four Na1+ and one P5+ atom. In the twenty-ninth O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one Fe2+, and one P5+ atom. In the thirtieth O2- site, O2- is bonded in a 1-coordinate geometry to four Na1+ and one P5+ atom. In the thirty-first O2- site, O2- is bonded in a 1-coordinate geometry to five Na1+ and one P5+ atom. In the thirty-second O2- site, O2- is bonded in a 1-coordinate geometry to two Na1+ and one P5+ atom.