The material described by Fe3(PO8)2 crystallizes in the triclinic P-1 space group. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent O(3), two equivalent O(4), and two equivalent O(6) atoms to form distorted FeO6 octahedra that share corners with two equivalent P(1)O4 tetrahedra. In the second Fe site, Fe(2) is bonded to one O(1), one O(2), one O(5), one O(8), and two equivalent O(7) atoms to form FeO6 octahedra that share corners with four equivalent P(1)O4 tetrahedra and  an edgeedge with one Fe(2)O6 octahedra. P(1) is bonded to one O(1), one O(2), one O(3), and one O(7) atom to form PO4 tetrahedra that share  a cornercorner with one Fe(1)O6 octahedra and corners with four equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 24-57°. 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 120 degrees geometry to one Fe(2) and one P(1) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Fe(1) and one P(1) atom. In the fourth O site, O(4) is bonded in a bent 120 degrees geometry to one Fe(1) and one O(6) atom. In the fifth O site, O(5) is bonded in a bent 120 degrees geometry to one Fe(2) and one O(6) atom. In the sixth O site, O(6) is bonded in a trigonal non-coplanar geometry to one Fe(1), one O(4), and one O(5) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to two equivalent Fe(2) and one P(1) atom. In the eighth O site, O(8) is bonded in a single-bond geometry to one Fe(2) atom. is represented by the CIF file [CIF]
data_Fe3(PO8)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.570
_cell_length_b   7.311
_cell_length_c   8.320
_cell_angle_alpha   99.954
_cell_angle_beta   91.740
_cell_angle_gamma   94.577
_symmetry_Int_Tables_number   1
_cell_volume   272.616
_cell_formula_units_Z   1
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  0.000  0.000  0.000  1.0
  Fe  Fe1  1  0.496  0.662  0.399  1.0
  Fe  Fe2  1  0.504  0.338  0.601  1.0
  P  P3  1  0.989  0.329  0.329  1.0
  P  P4  1  0.011  0.671  0.671  1.0
  O  O5  1  0.861  0.750  0.533  1.0
  O  O6  1  0.139  0.250  0.467  1.0
  O  O7  1  0.831  0.508  0.726  1.0
  O  O8  1  0.169  0.492  0.274  1.0
  O  O9  1  0.919  0.168  0.180  1.0
  O  O10  1  0.081  0.832  0.820  1.0
  O  O11  1  0.682  0.103  0.858  1.0
  O  O12  1  0.318  0.897  0.142  1.0
  O  O13  1  0.679  0.700  0.163  1.0
  O  O14  1  0.321  0.300  0.837  1.0
  O  O15  1  0.553  0.807  0.070  1.0
  O  O16  1  0.447  0.193  0.930  1.0
  O  O17  1  0.684  0.396  0.388  1.0
  O  O18  1  0.316  0.604  0.612  1.0
  O  O19  1  0.647  0.099  0.580  1.0
  O  O20  1  0.353  0.901  0.420  1.0
[/CIF]
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The material described by Fe3(PO8)2 crystallizes in the triclinic P-1 space group. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent O(3), two equivalent O(4), and two equivalent O(6) atoms to form distorted FeO6 octahedra that share corners with two equivalent P(1)O4 tetrahedra. In the second Fe site, Fe(2) is bonded to one O(1), one O(2), one O(5), one O(8), and two equivalent O(7) atoms to form FeO6 octahedra that share corners with four equivalent P(1)O4 tetrahedra and  an edgeedge with one Fe(2)O6 octahedra. P(1) is bonded to one O(1), one O(2), one O(3), and one O(7) atom to form PO4 tetrahedra that share  a cornercorner with one Fe(1)O6 octahedra and corners with four equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 24-57°. 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 120 degrees geometry to one Fe(2) and one P(1) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Fe(1) and one P(1) atom. In the fourth O site, O(4) is bonded in a bent 120 degrees geometry to one Fe(1) and one O(6) atom. In the fifth O site, O(5) is bonded in a bent 120 degrees geometry to one Fe(2) and one O(6) atom. In the sixth O site, O(6) is bonded in a trigonal non-coplanar geometry to one Fe(1), one O(4), and one O(5) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to two equivalent Fe(2) and one P(1) atom. In the eighth O site, O(8) is bonded in a single-bond geometry to one Fe(2) atom. is represented by the CIF file [CIF]
data_Fe3(PO8)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.570
_cell_length_b   7.311
_cell_length_c   8.320
_cell_angle_alpha   99.954
_cell_angle_beta   91.740
_cell_angle_gamma   94.577
_symmetry_Int_Tables_number   1
_cell_volume   272.616
_cell_formula_units_Z   1
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  0.000  0.000  0.000  1.0
  Fe  Fe1  1  0.496  0.662  0.399  1.0
  Fe  Fe2  1  0.504  0.338  0.601  1.0
  P  P3  1  0.989  0.329  0.329  1.0
  P  P4  1  0.011  0.671  0.671  1.0
  O  O5  1  0.861  0.750  0.533  1.0
  O  O6  1  0.139  0.250  0.467  1.0
  O  O7  1  0.831  0.508  0.726  1.0
  O  O8  1  0.169  0.492  0.274  1.0
  O  O9  1  0.919  0.168  0.180  1.0
  O  O10  1  0.081  0.832  0.820  1.0
  O  O11  1  0.682  0.103  0.858  1.0
  O  O12  1  0.318  0.897  0.142  1.0
  O  O13  1  0.679  0.700  0.163  1.0
  O  O14  1  0.321  0.300  0.837  1.0
  O  O15  1  0.553  0.807  0.070  1.0
  O  O16  1  0.447  0.193  0.930  1.0
  O  O17  1  0.684  0.396  0.388  1.0
  O  O18  1  0.316  0.604  0.612  1.0
  O  O19  1  0.647  0.099  0.580  1.0
  O  O20  1  0.353  0.901  0.420  1.0
[/CIF]
.