The material structure described by NaFe3(PO4)3 crystallizes in the monoclinic C2/c space group. Na(1) is bonded in a 4-coordinate geometry to four equivalent O(4) atoms. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one O(3), one O(4), one O(5), and two equivalent O(6) atoms to form FeO6 octahedra that share corners with two equivalent P(2)O4 tetrahedra, corners with four equivalent P(1)O4 tetrahedra,  an edgeedge with one Fe(1)O6 octahedra, and  an edgeedge with one Fe(2)O6 octahedra. In the second Fe site, Fe(2) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(5) atoms to form FeO6 octahedra that share corners with two equivalent P(2)O4 tetrahedra, corners with four equivalent P(1)O4 tetrahedra, and edges with two equivalent Fe(1)O6 octahedra. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(2), one O(3), one O(4), and one O(6) atom to form PO4 tetrahedra that share corners with two equivalent Fe(2)O6 octahedra and corners with four equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 38-61°. In the second P site, P(2) is bonded to two equivalent O(1) and two equivalent O(5) atoms to form PO4 tetrahedra that share corners with two equivalent Fe(2)O6 octahedra and corners with four equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 53-59°. There are six inequivalent O sites. In the first O site, O(4) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Na(1), one Fe(1), and one P(1) atom. In the second O site, O(5) is bonded in a 3-coordinate geometry to one Fe(1), one Fe(2), and one P(2) atom. In the third O site, O(6) is bonded in a 3-coordinate geometry to two equivalent Fe(1) and one P(1) atom. In the fourth O site, O(1) is bonded in a bent 120 degrees geometry to one Fe(1) and one P(2) atom. In the fifth O site, O(2) is bonded in a distorted bent 120 degrees geometry to one Fe(2) and one P(1) atom. In the sixth O site, O(3) is bonded in a 3-coordinate geometry to one Fe(1), one Fe(2), and one P(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_NaFe3(PO4)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.559
_cell_length_b   8.559
_cell_length_c   6.551
_cell_angle_alpha   73.797
_cell_angle_beta   73.797
_cell_angle_gamma   93.399
_symmetry_Int_Tables_number   1
_cell_volume   437.603
_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
  Na  Na0  1  0.019  0.981  0.250  1.0
  Na  Na1  1  0.981  0.019  0.750  1.0
  Fe  Fe2  1  0.621  0.946  0.122  1.0
  Fe  Fe3  1  0.379  0.054  0.878  1.0
  Fe  Fe4  1  0.283  0.717  0.750  1.0
  Fe  Fe5  1  0.054  0.379  0.378  1.0
  Fe  Fe6  1  0.717  0.283  0.250  1.0
  Fe  Fe7  1  0.946  0.621  0.622  1.0
  P  P8  1  0.884  0.662  0.112  1.0
  P  P9  1  0.662  0.884  0.612  1.0
  P  P10  1  0.116  0.338  0.888  1.0
  P  P11  1  0.338  0.116  0.388  1.0
  P  P12  1  0.690  0.310  0.750  1.0
  P  P13  1  0.310  0.690  0.250  1.0
  O  O14  1  0.512  0.270  0.762  1.0
  O  O15  1  0.475  0.256  0.347  1.0
  O  O16  1  0.525  0.744  0.653  1.0
  O  O17  1  0.981  0.315  0.120  1.0
  O  O18  1  0.685  0.019  0.380  1.0
  O  O19  1  0.256  0.475  0.847  1.0
  O  O20  1  0.488  0.730  0.238  1.0
  O  O21  1  0.019  0.685  0.880  1.0
  O  O22  1  0.166  0.166  0.900  1.0
  O  O23  1  0.197  0.726  0.467  1.0
  O  O24  1  0.274  0.803  0.033  1.0
  O  O25  1  0.803  0.274  0.533  1.0
  O  O26  1  0.744  0.525  0.153  1.0
  O  O27  1  0.166  0.166  0.400  1.0
  O  O28  1  0.834  0.834  0.600  1.0
  O  O29  1  0.730  0.488  0.738  1.0
  O  O30  1  0.035  0.389  0.699  1.0
  O  O31  1  0.270  0.512  0.262  1.0
  O  O32  1  0.726  0.197  0.967  1.0
  O  O33  1  0.389  0.035  0.199  1.0
  O  O34  1  0.834  0.834  0.100  1.0
  O  O35  1  0.315  0.981  0.620  1.0
  O  O36  1  0.965  0.611  0.301  1.0
  O  O37  1  0.611  0.965  0.801  1.0
[/CIF]
.
The material structure described by NaFe3(PO4)3 crystallizes in the monoclinic C2/c space group. Na(1) is bonded in a 4-coordinate geometry to four equivalent O(4) atoms. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one O(3), one O(4), one O(5), and two equivalent O(6) atoms to form FeO6 octahedra that share corners with two equivalent P(2)O4 tetrahedra, corners with four equivalent P(1)O4 tetrahedra,  an edgeedge with one Fe(1)O6 octahedra, and  an edgeedge with one Fe(2)O6 octahedra. In the second Fe site, Fe(2) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(5) atoms to form FeO6 octahedra that share corners with two equivalent P(2)O4 tetrahedra, corners with four equivalent P(1)O4 tetrahedra, and edges with two equivalent Fe(1)O6 octahedra. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(2), one O(3), one O(4), and one O(6) atom to form PO4 tetrahedra that share corners with two equivalent Fe(2)O6 octahedra and corners with four equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 38-61°. In the second P site, P(2) is bonded to two equivalent O(1) and two equivalent O(5) atoms to form PO4 tetrahedra that share corners with two equivalent Fe(2)O6 octahedra and corners with four equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 53-59°. There are six inequivalent O sites. In the first O site, O(4) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Na(1), one Fe(1), and one P(1) atom. In the second O site, O(5) is bonded in a 3-coordinate geometry to one Fe(1), one Fe(2), and one P(2) atom. In the third O site, O(6) is bonded in a 3-coordinate geometry to two equivalent Fe(1) and one P(1) atom. In the fourth O site, O(1) is bonded in a bent 120 degrees geometry to one Fe(1) and one P(2) atom. In the fifth O site, O(2) is bonded in a distorted bent 120 degrees geometry to one Fe(2) and one P(1) atom. In the sixth O site, O(3) is bonded in a 3-coordinate geometry to one Fe(1), one Fe(2), and one P(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_NaFe3(PO4)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.559
_cell_length_b   8.559
_cell_length_c   6.551
_cell_angle_alpha   73.797
_cell_angle_beta   73.797
_cell_angle_gamma   93.399
_symmetry_Int_Tables_number   1
_cell_volume   437.603
_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
  Na  Na0  1  0.019  0.981  0.250  1.0
  Na  Na1  1  0.981  0.019  0.750  1.0
  Fe  Fe2  1  0.621  0.946  0.122  1.0
  Fe  Fe3  1  0.379  0.054  0.878  1.0
  Fe  Fe4  1  0.283  0.717  0.750  1.0
  Fe  Fe5  1  0.054  0.379  0.378  1.0
  Fe  Fe6  1  0.717  0.283  0.250  1.0
  Fe  Fe7  1  0.946  0.621  0.622  1.0
  P  P8  1  0.884  0.662  0.112  1.0
  P  P9  1  0.662  0.884  0.612  1.0
  P  P10  1  0.116  0.338  0.888  1.0
  P  P11  1  0.338  0.116  0.388  1.0
  P  P12  1  0.690  0.310  0.750  1.0
  P  P13  1  0.310  0.690  0.250  1.0
  O  O14  1  0.512  0.270  0.762  1.0
  O  O15  1  0.475  0.256  0.347  1.0
  O  O16  1  0.525  0.744  0.653  1.0
  O  O17  1  0.981  0.315  0.120  1.0
  O  O18  1  0.685  0.019  0.380  1.0
  O  O19  1  0.256  0.475  0.847  1.0
  O  O20  1  0.488  0.730  0.238  1.0
  O  O21  1  0.019  0.685  0.880  1.0
  O  O22  1  0.166  0.166  0.900  1.0
  O  O23  1  0.197  0.726  0.467  1.0
  O  O24  1  0.274  0.803  0.033  1.0
  O  O25  1  0.803  0.274  0.533  1.0
  O  O26  1  0.744  0.525  0.153  1.0
  O  O27  1  0.166  0.166  0.400  1.0
  O  O28  1  0.834  0.834  0.600  1.0
  O  O29  1  0.730  0.488  0.738  1.0
  O  O30  1  0.035  0.389  0.699  1.0
  O  O31  1  0.270  0.512  0.262  1.0
  O  O32  1  0.726  0.197  0.967  1.0
  O  O33  1  0.389  0.035  0.199  1.0
  O  O34  1  0.834  0.834  0.100  1.0
  O  O35  1  0.315  0.981  0.620  1.0
  O  O36  1  0.965  0.611  0.301  1.0
  O  O37  1  0.611  0.965  0.801  1.0
[/CIF]
.