The structure described by Fe2(PO4)3 crystallizes in the trigonal R-3 space group. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to three equivalent O(1) and three equivalent O(4) atoms to form FeO6 octahedra that share corners with six equivalent P(1)O4 tetrahedra. In the second Fe site, Fe(2) is bonded to three equivalent O(2) and three equivalent O(3) atoms to form FeO6 octahedra that share corners with six equivalent P(1)O4 tetrahedra. P(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form PO4 tetrahedra that share corners with two equivalent Fe(1)O6 octahedra and corners with two equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 24-39°. There are four inequivalent O sites. In the first O site, O(3) is bonded in a bent 150 degrees geometry to one Fe(2) and one P(1) atom. In the second O site, O(4) is bonded in a bent 150 degrees geometry to one Fe(1) and one P(1) atom. In the third O site, O(1) is bonded in a bent 150 degrees geometry to one Fe(1) and one P(1) atom. In the fourth O site, O(2) is bonded in a bent 150 degrees geometry to one Fe(2) and one P(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Fe2(PO4)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.966
_cell_length_b   8.966
_cell_length_c   8.966
_cell_angle_alpha   56.521
_cell_angle_beta   56.521
_cell_angle_gamma   56.521
_symmetry_Int_Tables_number   1
_cell_volume   468.617
_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  0.354  0.354  0.354  1.0
  Fe  Fe1  1  0.646  0.646  0.646  1.0
  Fe  Fe2  1  0.141  0.141  0.141  1.0
  Fe  Fe3  1  0.859  0.859  0.859  1.0
  P  P4  1  0.745  0.468  0.037  1.0
  P  P5  1  0.037  0.745  0.468  1.0
  P  P6  1  0.963  0.255  0.532  1.0
  P  P7  1  0.255  0.532  0.963  1.0
  P  P8  1  0.532  0.963  0.255  1.0
  P  P9  1  0.468  0.037  0.745  1.0
  O  O10  1  0.516  0.156  0.230  1.0
  O  O11  1  0.624  0.007  0.794  1.0
  O  O12  1  0.268  0.111  0.887  1.0
  O  O13  1  0.889  0.113  0.732  1.0
  O  O14  1  0.376  0.993  0.206  1.0
  O  O15  1  0.732  0.889  0.113  1.0
  O  O16  1  0.111  0.887  0.268  1.0
  O  O17  1  0.794  0.624  0.007  1.0
  O  O18  1  0.230  0.516  0.156  1.0
  O  O19  1  0.510  0.820  0.461  1.0
  O  O20  1  0.844  0.770  0.484  1.0
  O  O21  1  0.539  0.490  0.180  1.0
  O  O22  1  0.007  0.794  0.624  1.0
  O  O23  1  0.887  0.268  0.111  1.0
  O  O24  1  0.770  0.484  0.844  1.0
  O  O25  1  0.180  0.539  0.490  1.0
  O  O26  1  0.820  0.461  0.510  1.0
  O  O27  1  0.206  0.376  0.993  1.0
  O  O28  1  0.113  0.732  0.889  1.0
  O  O29  1  0.993  0.206  0.376  1.0
  O  O30  1  0.461  0.510  0.820  1.0
  O  O31  1  0.156  0.230  0.516  1.0
  O  O32  1  0.490  0.180  0.539  1.0
  O  O33  1  0.484  0.844  0.770  1.0
[/CIF]
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The structure described by Fe2(PO4)3 crystallizes in the trigonal R-3 space group. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to three equivalent O(1) and three equivalent O(4) atoms to form FeO6 octahedra that share corners with six equivalent P(1)O4 tetrahedra. In the second Fe site, Fe(2) is bonded to three equivalent O(2) and three equivalent O(3) atoms to form FeO6 octahedra that share corners with six equivalent P(1)O4 tetrahedra. P(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form PO4 tetrahedra that share corners with two equivalent Fe(1)O6 octahedra and corners with two equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 24-39°. There are four inequivalent O sites. In the first O site, O(3) is bonded in a bent 150 degrees geometry to one Fe(2) and one P(1) atom. In the second O site, O(4) is bonded in a bent 150 degrees geometry to one Fe(1) and one P(1) atom. In the third O site, O(1) is bonded in a bent 150 degrees geometry to one Fe(1) and one P(1) atom. In the fourth O site, O(2) is bonded in a bent 150 degrees geometry to one Fe(2) and one P(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Fe2(PO4)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.966
_cell_length_b   8.966
_cell_length_c   8.966
_cell_angle_alpha   56.521
_cell_angle_beta   56.521
_cell_angle_gamma   56.521
_symmetry_Int_Tables_number   1
_cell_volume   468.617
_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  0.354  0.354  0.354  1.0
  Fe  Fe1  1  0.646  0.646  0.646  1.0
  Fe  Fe2  1  0.141  0.141  0.141  1.0
  Fe  Fe3  1  0.859  0.859  0.859  1.0
  P  P4  1  0.745  0.468  0.037  1.0
  P  P5  1  0.037  0.745  0.468  1.0
  P  P6  1  0.963  0.255  0.532  1.0
  P  P7  1  0.255  0.532  0.963  1.0
  P  P8  1  0.532  0.963  0.255  1.0
  P  P9  1  0.468  0.037  0.745  1.0
  O  O10  1  0.516  0.156  0.230  1.0
  O  O11  1  0.624  0.007  0.794  1.0
  O  O12  1  0.268  0.111  0.887  1.0
  O  O13  1  0.889  0.113  0.732  1.0
  O  O14  1  0.376  0.993  0.206  1.0
  O  O15  1  0.732  0.889  0.113  1.0
  O  O16  1  0.111  0.887  0.268  1.0
  O  O17  1  0.794  0.624  0.007  1.0
  O  O18  1  0.230  0.516  0.156  1.0
  O  O19  1  0.510  0.820  0.461  1.0
  O  O20  1  0.844  0.770  0.484  1.0
  O  O21  1  0.539  0.490  0.180  1.0
  O  O22  1  0.007  0.794  0.624  1.0
  O  O23  1  0.887  0.268  0.111  1.0
  O  O24  1  0.770  0.484  0.844  1.0
  O  O25  1  0.180  0.539  0.490  1.0
  O  O26  1  0.820  0.461  0.510  1.0
  O  O27  1  0.206  0.376  0.993  1.0
  O  O28  1  0.113  0.732  0.889  1.0
  O  O29  1  0.993  0.206  0.376  1.0
  O  O30  1  0.461  0.510  0.820  1.0
  O  O31  1  0.156  0.230  0.516  1.0
  O  O32  1  0.490  0.180  0.539  1.0
  O  O33  1  0.484  0.844  0.770  1.0
[/CIF]
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