DOE OSTI2020
Na2FeCPO7 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 2.40–2.79 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 2.38–2.80 Å. In the third 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 2.39–2.89 Å. In the fourth Na1+ site, Na1+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Na–O bond distances ranging from 2.25–2.83 Å. In the fifth Na1+ site, Na1+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Na–O bond distances ranging from 2.25–2.82 Å. In the sixth Na1+ site, Na1+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Na–O bond distances ranging from 2.27–2.81 Å. In the seventh Na1+ site, Na1+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Na–O bond distances ranging from 2.24–2.85 Å. In the eighth Na1+ site, Na1+ is bonded to seven O2- atoms to form distorted NaO7 pentagonal bipyramids that share a cornercorner with one FeO6 octahedra, corners with two equivalent NaO7 pentagonal bipyramids, corners with two PO4 tetrahedra, an edgeedge with one FeO6 octahedra, edges with two equivalent NaO6 octahedra, an edgeedge with one PO4 tetrahedra, and a faceface with one FeO6 octahedra. The corner-sharing octahedral tilt angles are 66°. There are a spread of Na–O bond distances ranging from 2.30–2.80 Å. In the ninth Na1+ site, Na1+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Na–O bond distances ranging from 2.25–2.83 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 2.37–2.81 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 2.39–2.80 Å. In the twelfth Na1+ site, Na1+ is bonded to six O2- atoms to form distorted NaO6 octahedra that share corners with two equivalent NaO6 octahedra, corners with four FeO6 octahedra, edges with two equivalent NaO7 pentagonal bipyramids, and an edgeedge with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 0–56°. There are a spread of Na–O bond distances ranging from 2.28–2.83 Å. There are six inequivalent Fe3+ sites. In the first Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with four PO4 tetrahedra. There are a spread of Fe–O bond distances ranging from 1.97–2.13 Å. In the second Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with four PO4 tetrahedra. There are a spread of Fe–O bond distances ranging from 1.98–2.13 Å. In the third Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with two equivalent NaO6 octahedra, a cornercorner with one NaO7 pentagonal bipyramid, and corners with four PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 0–18°. There are a spread of Fe–O bond distances ranging from 1.96–2.17 Å. In the fourth Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share a cornercorner with one NaO6 octahedra, corners with four PO4 tetrahedra, an edgeedge with one NaO7 pentagonal bipyramid, and a faceface with one NaO7 pentagonal bipyramid. The corner-sharing octahedral tilt angles are 56°. There are a spread of Fe–O bond distances ranging from 1.96–2.15 Å. In the fifth Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with four PO4 tetrahedra. There are a spread of Fe–O bond distances ranging from 1.98–2.14 Å. In the sixth Fe3+ site, Fe3+ is bonded to six O2- atoms to form distorted FeO6 octahedra that share a cornercorner with one NaO6 octahedra and corners with four PO4 tetrahedra. The corner-sharing octahedral tilt angles are 55°. There are a spread of Fe–O bond distances ranging from 1.90–2.15 Å. There are six inequivalent C4+ sites. In the first C4+ site, C4+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of C–O bond distances ranging from 1.27–1.32 Å. In the second C4+ site, C4+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of C–O bond distances ranging from 1.27–1.32 Å. In the third C4+ site, C4+ is bonded in a trigonal planar geometry to three O2- atoms. There is one shorter (1.29 Å) and two longer (1.30 Å) C–O bond length. In the fourth C4+ site, C4+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of C–O bond distances ranging from 1.27–1.32 Å. In the fifth C4+ site, C4+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of C–O bond distances ranging from 1.27–1.32 Å. In the sixth C4+ site, C4+ is bonded in a trigonal planar geometry to three O2- atoms. There is one shorter (1.25 Å) and two longer (1.33 Å) C–O bond length. There are six inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with four FeO6 octahedra. The corner-sharing octahedra tilt angles range from 37–41°. There are a spread of P–O bond distances ranging from 1.53–1.57 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with four FeO6 octahedra. The corner-sharing octahedra tilt angles range from 34–43°. There are a spread of P–O bond distances ranging from 1.54–1.56 Å. In the third P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with four FeO6 octahedra and a cornercorner with one NaO7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 33–42°. There are a spread of P–O bond distances ranging from 1.54–1.56 Å. In the fourth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with four FeO6 octahedra. The corner-sharing octahedra tilt angles range from 34–43°. There are a spread of P–O bond distances ranging from 1.54–1.56 Å. In the fifth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with four FeO6 octahedra, a cornercorner with one NaO7 pentagonal bipyramid, an edgeedge with one NaO6 octahedra, and an edgeedge with one NaO7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 31–46°. There are a spread of P–O bond distances ranging from 1.53–1.57 Å. In the sixth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with four FeO6 octahedra. The corner-sharing octahedra tilt angles range from 34–45°. There are a spread of P–O bond distances ranging from 1.54–1.56 Å. There are forty-two inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to three Na1+ and one C4+ atom. In the second O2- site, O2- is bonded in a 4-coordinate geometry to three Na1+ and one C4+ atom. In the third O2- site, O2- is bonded in a distorted single-bond geometry to two equivalent Na1+ and one C4+ atom. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one Fe3+, and one C4+ atom. In the fifth O2- site, O2- is bonded in a 1-coordinate geometry to two Na1+, one Fe3+, and one C4+ atom. In the sixth O2- site, O2- is bonded in a distorted T-shaped geometry to one Na1+, one Fe3+, and one C4+ atom. In the seventh O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one Fe3+, and one C4+ atom. In the eighth O2- site, O2- is bonded in a 1-coordinate geometry to two Na1+, one Fe3+, and one C4+ atom. In the ninth O2- site, O2- is bonded in a distorted T-shaped geometry to one Na1+, one Fe3+, and one C4+ atom. In the tenth O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Fe3+, and one P5+ atom. In the eleventh O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Fe3+, and one P5+ atom. In the twelfth O2- site, O2- is bonded in a 1-coordinate geometry to three Na1+, one Fe3+, and one P5+ atom. In the thirteenth O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Fe3+, and one P5+ atom. In the fourteenth O2- site, O2- is bonded in a 1-coordinate geometry to three Na1+, one Fe3+, and one P5+ atom. In the fifteenth O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Fe3+, and one P5+ atom. In the sixteenth O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Fe3+, and one P5+ atom. In the seventeenth O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Fe3+, and one P5+ atom. In the eighteenth O2- site, O2- is bonded in a bent 150 degrees geometry to one Fe3+ and one P5+ atom. In the nineteenth O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Fe3+, and one P5+ atom. In the twentieth O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Fe3+, and one P5+ atom. In the twenty-first O2- site, O2- is bonded in a bent 150 degrees geometry to one Fe3+ and one P5+ atom. In the twenty-second O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Fe3+, and one P5+ atom. In the twenty-third O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Fe3+, and one P5+ atom. In the twenty-fourth O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one Fe3+, and one P5+ atom. In the twenty-fifth O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Fe3+, and one P5+ atom. In the twenty-sixth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two Na1+, one Fe3+, and one P5+ atom. In the twenty-seventh O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Fe3+, and one P5+ atom. In the twenty-eighth O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Fe3+, and one P5+ atom. In the twenty-ninth O2- site, O2- is bonded in a 1-coordinate geometry to three Na1+, one Fe3+, and one P5+ atom. In the thirtieth O2- site, O2- is bonded in a 1-coordinate geometry to three Na1+, one Fe3+, and one P5+ atom. In the thirty-first O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Fe3+, and one P5+ atom. In the thirty-second O2- site, O2- is bonded in a 1-coordinate geometry to three Na1+, one Fe3+, and one P5+ atom. In the thirty-third O2- site, O2- is bonded in a 1-coordinate geometry to three Na1+, one Fe3+, and one P5+ atom. In the thirty-fourth O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one Fe3+, and one C4+ atom. In the thirty-fifth O2- site, O2- is bonded in a 1-coordinate geometry to two Na1+, one Fe3+, and one C4+ atom. In the thirty-sixth O2- site, O2- is bonded in a 1-coordinate geometry to three Na1+, one Fe3+, and one C4+ atom. In the thirty-seventh O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two Na1+, one Fe3+, and one C4+ atom. In the thirty-eighth O2- site, O2- is bonded in a 1-coordinate geometry to two Na1+, one Fe3+, and one C4+ atom. In the thirty-ninth O2- site, O2- is bonded in a 1-coordinate geometry to three Na1+, one Fe3+, and one C4+ atom. In the fortieth O2- site, O2- is bonded in a 4-coordinate geometry to three Na1+ and one C4+ atom. In the forty-first O2- site, O2- is bonded in a 4-coordinate geometry to three Na1+ and one C4+ atom. In the forty-second O2- site, O2- is bonded in a 5-coordinate geometry to four Na1+ and one C4+ atom.