The crystal structure described by FePO4 crystallizes in the monoclinic C2/c space group. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(2), one O(3), one O(4), one O(6), and one O(7) atom to form distorted FeO5 square pyramids that share corners with two equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra, and  an edgeedge with one Fe(3)O6 octahedra. In the second Fe site, Fe(2) is bonded in a square co-planar geometry to two equivalent O(1) and two equivalent O(4) atoms. In the third Fe site, Fe(3) is bonded to two equivalent O(5), two equivalent O(6), and two equivalent O(7) atoms to form distorted FeO6 octahedra that share corners with two equivalent P(1)O4 tetrahedra, corners with four equivalent P(2)O4 tetrahedra, and edges with two equivalent Fe(1)O5 square pyramids. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(4), one O(7), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one Fe(3)O6 octahedra and corners with two equivalent Fe(1)O5 square pyramids. The corner-sharing octahedral tilt angles are 54°. In the second P site, P(2) is bonded to one O(2), one O(3), one O(5), and one O(6) atom to form PO4 tetrahedra that share corners with two equivalent Fe(3)O6 octahedra and corners with three equivalent Fe(1)O5 square pyramids. The corner-sharing octahedral tilt angles range from 42-51°. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 120 degrees geometry to one Fe(2) and one P(1) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Fe(1) and one P(2) atom. In the third O site, O(3) is bonded in a bent 120 degrees geometry to one Fe(1) and one P(2) atom. In the fourth O site, O(4) is bonded in a trigonal planar geometry to one Fe(1), one Fe(2), and one P(1) atom. In the fifth O site, O(5) is bonded in a bent 120 degrees geometry to one Fe(3) and one P(2) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Fe(1), one Fe(3), and one P(2) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Fe(1), one Fe(3), and one P(1) atom. In the eighth O site, O(8) is bonded in a single-bond geometry to one P(1) atom. is represented by the CIF file [CIF]
data_FePO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.295
_cell_length_b   9.295
_cell_length_c   15.722
_cell_angle_alpha   62.445
_cell_angle_beta   62.445
_cell_angle_gamma   31.273
_symmetry_Int_Tables_number   1
_cell_volume   618.447
_cell_formula_units_Z   8
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
  Fe  Fe0  1  0.409  0.798  0.523  1.0
  Fe  Fe1  1  0.202  0.591  0.977  1.0
  Fe  Fe2  1  0.591  0.202  0.477  1.0
  Fe  Fe3  1  0.000  0.500  0.500  1.0
  Fe  Fe4  1  0.798  0.409  0.023  1.0
  Fe  Fe5  1  0.673  0.327  0.250  1.0
  Fe  Fe6  1  0.327  0.673  0.750  1.0
  Fe  Fe7  1  0.500  0.000  0.000  1.0
  P  P8  1  0.486  0.940  0.644  1.0
  P  P9  1  0.811  0.223  0.879  1.0
  P  P10  1  0.514  0.060  0.356  1.0
  P  P11  1  0.223  0.811  0.379  1.0
  P  P12  1  0.940  0.486  0.144  1.0
  P  P13  1  0.060  0.514  0.856  1.0
  P  P14  1  0.189  0.777  0.121  1.0
  P  P15  1  0.777  0.189  0.621  1.0
  O  O16  1  0.199  0.293  0.403  1.0
  O  O17  1  0.717  0.140  0.571  1.0
  O  O18  1  0.293  0.199  0.903  1.0
  O  O19  1  0.608  0.242  0.949  1.0
  O  O20  1  0.649  0.800  0.444  1.0
  O  O21  1  0.678  0.432  0.787  1.0
  O  O22  1  0.758  0.392  0.551  1.0
  O  O23  1  0.908  0.100  0.361  1.0
  O  O24  1  0.392  0.758  0.051  1.0
  O  O25  1  0.860  0.283  0.929  1.0
  O  O26  1  0.622  0.127  0.363  1.0
  O  O27  1  0.998  0.405  0.240  1.0
  O  O28  1  0.283  0.860  0.429  1.0
  O  O29  1  0.100  0.908  0.861  1.0
  O  O30  1  0.801  0.707  0.597  1.0
  O  O31  1  0.378  0.873  0.637  1.0
  O  O32  1  0.405  0.998  0.740  1.0
  O  O33  1  0.242  0.608  0.449  1.0
  O  O34  1  0.127  0.622  0.863  1.0
  O  O35  1  0.002  0.595  0.760  1.0
  O  O36  1  0.900  0.092  0.139  1.0
  O  O37  1  0.800  0.649  0.944  1.0
  O  O38  1  0.092  0.900  0.639  1.0
  O  O39  1  0.432  0.678  0.287  1.0
  O  O40  1  0.140  0.717  0.071  1.0
  O  O41  1  0.707  0.801  0.097  1.0
  O  O42  1  0.595  0.002  0.260  1.0
  O  O43  1  0.200  0.351  0.056  1.0
  O  O44  1  0.351  0.200  0.556  1.0
  O  O45  1  0.568  0.322  0.713  1.0
  O  O46  1  0.322  0.568  0.213  1.0
  O  O47  1  0.873  0.378  0.137  1.0
[/CIF]
.
The crystal structure described by FePO4 crystallizes in the monoclinic C2/c space group. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(2), one O(3), one O(4), one O(6), and one O(7) atom to form distorted FeO5 square pyramids that share corners with two equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra, and  an edgeedge with one Fe(3)O6 octahedra. In the second Fe site, Fe(2) is bonded in a square co-planar geometry to two equivalent O(1) and two equivalent O(4) atoms. In the third Fe site, Fe(3) is bonded to two equivalent O(5), two equivalent O(6), and two equivalent O(7) atoms to form distorted FeO6 octahedra that share corners with two equivalent P(1)O4 tetrahedra, corners with four equivalent P(2)O4 tetrahedra, and edges with two equivalent Fe(1)O5 square pyramids. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(4), one O(7), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one Fe(3)O6 octahedra and corners with two equivalent Fe(1)O5 square pyramids. The corner-sharing octahedral tilt angles are 54°. In the second P site, P(2) is bonded to one O(2), one O(3), one O(5), and one O(6) atom to form PO4 tetrahedra that share corners with two equivalent Fe(3)O6 octahedra and corners with three equivalent Fe(1)O5 square pyramids. The corner-sharing octahedral tilt angles range from 42-51°. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 120 degrees geometry to one Fe(2) and one P(1) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Fe(1) and one P(2) atom. In the third O site, O(3) is bonded in a bent 120 degrees geometry to one Fe(1) and one P(2) atom. In the fourth O site, O(4) is bonded in a trigonal planar geometry to one Fe(1), one Fe(2), and one P(1) atom. In the fifth O site, O(5) is bonded in a bent 120 degrees geometry to one Fe(3) and one P(2) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Fe(1), one Fe(3), and one P(2) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Fe(1), one Fe(3), and one P(1) atom. In the eighth O site, O(8) is bonded in a single-bond geometry to one P(1) atom. is represented by the CIF file [CIF]
data_FePO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.295
_cell_length_b   9.295
_cell_length_c   15.722
_cell_angle_alpha   62.445
_cell_angle_beta   62.445
_cell_angle_gamma   31.273
_symmetry_Int_Tables_number   1
_cell_volume   618.447
_cell_formula_units_Z   8
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
  Fe  Fe0  1  0.409  0.798  0.523  1.0
  Fe  Fe1  1  0.202  0.591  0.977  1.0
  Fe  Fe2  1  0.591  0.202  0.477  1.0
  Fe  Fe3  1  0.000  0.500  0.500  1.0
  Fe  Fe4  1  0.798  0.409  0.023  1.0
  Fe  Fe5  1  0.673  0.327  0.250  1.0
  Fe  Fe6  1  0.327  0.673  0.750  1.0
  Fe  Fe7  1  0.500  0.000  0.000  1.0
  P  P8  1  0.486  0.940  0.644  1.0
  P  P9  1  0.811  0.223  0.879  1.0
  P  P10  1  0.514  0.060  0.356  1.0
  P  P11  1  0.223  0.811  0.379  1.0
  P  P12  1  0.940  0.486  0.144  1.0
  P  P13  1  0.060  0.514  0.856  1.0
  P  P14  1  0.189  0.777  0.121  1.0
  P  P15  1  0.777  0.189  0.621  1.0
  O  O16  1  0.199  0.293  0.403  1.0
  O  O17  1  0.717  0.140  0.571  1.0
  O  O18  1  0.293  0.199  0.903  1.0
  O  O19  1  0.608  0.242  0.949  1.0
  O  O20  1  0.649  0.800  0.444  1.0
  O  O21  1  0.678  0.432  0.787  1.0
  O  O22  1  0.758  0.392  0.551  1.0
  O  O23  1  0.908  0.100  0.361  1.0
  O  O24  1  0.392  0.758  0.051  1.0
  O  O25  1  0.860  0.283  0.929  1.0
  O  O26  1  0.622  0.127  0.363  1.0
  O  O27  1  0.998  0.405  0.240  1.0
  O  O28  1  0.283  0.860  0.429  1.0
  O  O29  1  0.100  0.908  0.861  1.0
  O  O30  1  0.801  0.707  0.597  1.0
  O  O31  1  0.378  0.873  0.637  1.0
  O  O32  1  0.405  0.998  0.740  1.0
  O  O33  1  0.242  0.608  0.449  1.0
  O  O34  1  0.127  0.622  0.863  1.0
  O  O35  1  0.002  0.595  0.760  1.0
  O  O36  1  0.900  0.092  0.139  1.0
  O  O37  1  0.800  0.649  0.944  1.0
  O  O38  1  0.092  0.900  0.639  1.0
  O  O39  1  0.432  0.678  0.287  1.0
  O  O40  1  0.140  0.717  0.071  1.0
  O  O41  1  0.707  0.801  0.097  1.0
  O  O42  1  0.595  0.002  0.260  1.0
  O  O43  1  0.200  0.351  0.056  1.0
  O  O44  1  0.351  0.200  0.556  1.0
  O  O45  1  0.568  0.322  0.713  1.0
  O  O46  1  0.322  0.568  0.213  1.0
  O  O47  1  0.873  0.378  0.137  1.0
[/CIF]
.