The compound described by Fe2(PO4)O crystallizes in the monoclinic C2/c space group. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form FeO6 octahedra that share corners with two equivalent Fe(1)O6 octahedra, corners with two equivalent Fe(2)O6 octahedra, corners with four equivalent P(1)O4 tetrahedra, and faces with two equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 55-61°. In the second Fe site, Fe(2) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form FeO6 octahedra that share corners with two equivalent Fe(1)O6 octahedra, corners with two equivalent Fe(2)O6 octahedra, corners with four equivalent P(1)O4 tetrahedra, and faces with two equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 49-55°. P(1) is bonded to two equivalent O(2) and two equivalent O(3) atoms to form PO4 tetrahedra that share corners with four equivalent Fe(1)O6 octahedra and corners with four equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 38-45°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to two equivalent Fe(1) and two equivalent Fe(2) atoms. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Fe(1), one Fe(2), and one P(1) atom. In the third 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 CIF file [CIF]
data_Fe2PO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.440
_cell_length_b   5.440
_cell_length_c   7.376
_cell_angle_alpha   68.153
_cell_angle_beta   111.848
_cell_angle_gamma   89.838
_symmetry_Int_Tables_number   1
_cell_volume   185.521
_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
  Fe  Fe0  1  0.500  1.000  0.500  1.0
  Fe  Fe1  1  1.000  0.000  0.500  1.0
  Fe  Fe2  1  0.500  0.000  1.000  1.0
  Fe  Fe3  1  0.500  0.500  0.000  1.0
  P  P4  1  0.877  0.377  0.750  1.0
  P  P5  1  0.123  0.623  0.250  1.0
  O  O6  1  0.642  0.142  0.250  1.0
  O  O7  1  0.358  0.858  0.750  1.0
  O  O8  1  0.823  0.192  0.628  1.0
  O  O9  1  0.692  0.323  0.872  1.0
  O  O10  1  0.180  0.311  0.897  1.0
  O  O11  1  0.177  0.808  0.372  1.0
  O  O12  1  0.811  0.680  0.603  1.0
  O  O13  1  0.820  0.689  0.103  1.0
  O  O14  1  0.308  0.677  0.128  1.0
  O  O15  1  0.189  0.320  0.397  1.0
[/CIF]
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The compound described by Fe2(PO4)O crystallizes in the monoclinic C2/c space group. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form FeO6 octahedra that share corners with two equivalent Fe(1)O6 octahedra, corners with two equivalent Fe(2)O6 octahedra, corners with four equivalent P(1)O4 tetrahedra, and faces with two equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 55-61°. In the second Fe site, Fe(2) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form FeO6 octahedra that share corners with two equivalent Fe(1)O6 octahedra, corners with two equivalent Fe(2)O6 octahedra, corners with four equivalent P(1)O4 tetrahedra, and faces with two equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 49-55°. P(1) is bonded to two equivalent O(2) and two equivalent O(3) atoms to form PO4 tetrahedra that share corners with four equivalent Fe(1)O6 octahedra and corners with four equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 38-45°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to two equivalent Fe(1) and two equivalent Fe(2) atoms. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Fe(1), one Fe(2), and one P(1) atom. In the third 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 CIF file [CIF]
data_Fe2PO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.440
_cell_length_b   5.440
_cell_length_c   7.376
_cell_angle_alpha   68.153
_cell_angle_beta   111.848
_cell_angle_gamma   89.838
_symmetry_Int_Tables_number   1
_cell_volume   185.521
_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
  Fe  Fe0  1  0.500  1.000  0.500  1.0
  Fe  Fe1  1  1.000  0.000  0.500  1.0
  Fe  Fe2  1  0.500  0.000  1.000  1.0
  Fe  Fe3  1  0.500  0.500  0.000  1.0
  P  P4  1  0.877  0.377  0.750  1.0
  P  P5  1  0.123  0.623  0.250  1.0
  O  O6  1  0.642  0.142  0.250  1.0
  O  O7  1  0.358  0.858  0.750  1.0
  O  O8  1  0.823  0.192  0.628  1.0
  O  O9  1  0.692  0.323  0.872  1.0
  O  O10  1  0.180  0.311  0.897  1.0
  O  O11  1  0.177  0.808  0.372  1.0
  O  O12  1  0.811  0.680  0.603  1.0
  O  O13  1  0.820  0.689  0.103  1.0
  O  O14  1  0.308  0.677  0.128  1.0
  O  O15  1  0.189  0.320  0.397  1.0
[/CIF]
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