The compound described by Na4NiP2O7F2 crystallizes in the orthorhombic Imma space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 6-coordinate geometry to two equivalent O(2), two equivalent O(3), and two equivalent F(2) atoms. In the second Na site, Na(2) is bonded in a 5-coordinate geometry to one O(2), two equivalent O(3), one F(1), and one F(2) atom. Ni(1) is bonded to four equivalent O(3) and two equivalent F(1) atoms to form NiO4F2 octahedra that share corners with two equivalent Ni(1)O4F2 octahedra and corners with four equivalent P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 54°. P(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form PO4 tetrahedra that share corners with two equivalent Ni(1)O4F2 octahedra and  a cornercorner with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 58°. There are three inequivalent O sites. In the first O site, O(3) is bonded in a 4-coordinate geometry to one Na(1), one Na(2), one Ni(1), and one P(1) atom. In the second O site, O(1) is bonded in a bent 120 degrees geometry to two equivalent P(1) atoms. In the third O site, O(2) is bonded in a rectangular see-saw-like geometry to one Na(2), two equivalent Na(1), and one P(1) atom. There are two inequivalent F sites. In the first F site, F(1) is bonded to two equivalent Na(2) and two equivalent Ni(1) atoms to form FNa2Ni2 tetrahedra that share corners with two equivalent F(2)Na6 octahedra and corners with two equivalent F(1)Na2Ni2 tetrahedra. The corner-sharing octahedral tilt angles are 51°. In the second F site, F(2) is bonded to two equivalent Na(2) and four equivalent Na(1) atoms to form FNa6 octahedra that share corners with four equivalent F(2)Na6 octahedra and corners with two equivalent F(1)Na2Ni2 tetrahedra. The corner-sharing octahedral tilt angles are 11°. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na4NiP2O7F2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.157
_cell_length_b   7.860
_cell_length_c   9.254
_cell_angle_alpha   115.133
_cell_angle_beta   112.749
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   426.189
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
loop_
 _atom_site_type_symbol
 _atom_site_label
 _atom_site_symmetry_multiplicity
 _atom_site_fract_x
 _atom_site_fract_y
 _atom_site_fract_z
 _atom_site_occupancy
  F  F0  1  0.250  0.116  0.000  1.0
  F  F1  1  0.750  0.884  1.000  1.0
  F  F2  1  0.500  0.500  0.500  1.0
  F  F3  1  1.000  0.000  0.500  1.0
  Na  Na4  1  0.266  0.766  0.533  1.0
  Na  Na5  1  0.766  0.766  0.533  1.0
  Na  Na6  1  0.734  0.234  0.467  1.0
  Na  Na7  1  0.234  0.234  0.467  1.0
  Na  Na8  1  0.639  0.590  0.778  1.0
  Na  Na9  1  0.139  0.187  0.778  1.0
  Na  Na10  1  0.361  0.410  0.222  1.0
  Na  Na11  1  0.861  0.813  0.222  1.0
  Ni  Ni12  1  1.000  1.000  1.000  1.0
  Ni  Ni13  1  0.500  0.000  0.000  1.0
  O  O14  1  0.250  0.622  0.000  1.0
  O  O15  1  0.750  0.378  1.000  1.0
  O  O16  1  0.086  0.412  0.671  1.0
  O  O17  1  0.586  0.259  0.671  1.0
  O  O18  1  0.914  0.588  0.329  1.0
  O  O19  1  0.414  0.741  0.329  1.0
  O  O20  1  0.171  0.929  0.200  1.0
  O  O21  1  0.029  0.271  0.200  1.0
  O  O22  1  0.671  0.271  0.200  1.0
  O  O23  1  0.529  0.929  0.200  1.0
  O  O24  1  0.829  0.071  0.800  1.0
  O  O25  1  0.971  0.729  0.800  1.0
  O  O26  1  0.329  0.729  0.800  1.0
  O  O27  1  0.471  0.071  0.800  1.0
  P  P28  1  0.347  0.817  0.194  1.0
  P  P29  1  0.847  0.377  0.194  1.0
  P  P30  1  0.653  0.183  0.806  1.0
  P  P31  1  0.153  0.623  0.806  1.0
[/CIF]
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The compound described by Na4NiP2O7F2 crystallizes in the orthorhombic Imma space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 6-coordinate geometry to two equivalent O(2), two equivalent O(3), and two equivalent F(2) atoms. In the second Na site, Na(2) is bonded in a 5-coordinate geometry to one O(2), two equivalent O(3), one F(1), and one F(2) atom. Ni(1) is bonded to four equivalent O(3) and two equivalent F(1) atoms to form NiO4F2 octahedra that share corners with two equivalent Ni(1)O4F2 octahedra and corners with four equivalent P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 54°. P(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form PO4 tetrahedra that share corners with two equivalent Ni(1)O4F2 octahedra and  a cornercorner with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 58°. There are three inequivalent O sites. In the first O site, O(3) is bonded in a 4-coordinate geometry to one Na(1), one Na(2), one Ni(1), and one P(1) atom. In the second O site, O(1) is bonded in a bent 120 degrees geometry to two equivalent P(1) atoms. In the third O site, O(2) is bonded in a rectangular see-saw-like geometry to one Na(2), two equivalent Na(1), and one P(1) atom. There are two inequivalent F sites. In the first F site, F(1) is bonded to two equivalent Na(2) and two equivalent Ni(1) atoms to form FNa2Ni2 tetrahedra that share corners with two equivalent F(2)Na6 octahedra and corners with two equivalent F(1)Na2Ni2 tetrahedra. The corner-sharing octahedral tilt angles are 51°. In the second F site, F(2) is bonded to two equivalent Na(2) and four equivalent Na(1) atoms to form FNa6 octahedra that share corners with four equivalent F(2)Na6 octahedra and corners with two equivalent F(1)Na2Ni2 tetrahedra. The corner-sharing octahedral tilt angles are 11°. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na4NiP2O7F2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.157
_cell_length_b   7.860
_cell_length_c   9.254
_cell_angle_alpha   115.133
_cell_angle_beta   112.749
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   426.189
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
loop_
 _atom_site_type_symbol
 _atom_site_label
 _atom_site_symmetry_multiplicity
 _atom_site_fract_x
 _atom_site_fract_y
 _atom_site_fract_z
 _atom_site_occupancy
  F  F0  1  0.250  0.116  0.000  1.0
  F  F1  1  0.750  0.884  1.000  1.0
  F  F2  1  0.500  0.500  0.500  1.0
  F  F3  1  1.000  0.000  0.500  1.0
  Na  Na4  1  0.266  0.766  0.533  1.0
  Na  Na5  1  0.766  0.766  0.533  1.0
  Na  Na6  1  0.734  0.234  0.467  1.0
  Na  Na7  1  0.234  0.234  0.467  1.0
  Na  Na8  1  0.639  0.590  0.778  1.0
  Na  Na9  1  0.139  0.187  0.778  1.0
  Na  Na10  1  0.361  0.410  0.222  1.0
  Na  Na11  1  0.861  0.813  0.222  1.0
  Ni  Ni12  1  1.000  1.000  1.000  1.0
  Ni  Ni13  1  0.500  0.000  0.000  1.0
  O  O14  1  0.250  0.622  0.000  1.0
  O  O15  1  0.750  0.378  1.000  1.0
  O  O16  1  0.086  0.412  0.671  1.0
  O  O17  1  0.586  0.259  0.671  1.0
  O  O18  1  0.914  0.588  0.329  1.0
  O  O19  1  0.414  0.741  0.329  1.0
  O  O20  1  0.171  0.929  0.200  1.0
  O  O21  1  0.029  0.271  0.200  1.0
  O  O22  1  0.671  0.271  0.200  1.0
  O  O23  1  0.529  0.929  0.200  1.0
  O  O24  1  0.829  0.071  0.800  1.0
  O  O25  1  0.971  0.729  0.800  1.0
  O  O26  1  0.329  0.729  0.800  1.0
  O  O27  1  0.471  0.071  0.800  1.0
  P  P28  1  0.347  0.817  0.194  1.0
  P  P29  1  0.847  0.377  0.194  1.0
  P  P30  1  0.653  0.183  0.806  1.0
  P  P31  1  0.153  0.623  0.806  1.0
[/CIF]
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