The crystal structure described by FeP2O7 crystallizes in the monoclinic C2 space group. Fe(1) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(4) 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 three equivalent Fe(1)O6 octahedra and  a cornercorner with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 15-49°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a bent 120 degrees geometry to two equivalent P(1) atoms. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to one Fe(1) and one P(1) atom. In the third O site, O(3) is bonded in a linear geometry to one Fe(1) and one P(1) atom. In the fourth O site, O(4) is bonded in a distorted bent 120 degrees geometry to one Fe(1) and one P(1) atom. is represented by the CIF file [CIF]
data_FeP2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.236
_cell_length_b   5.236
_cell_length_c   4.608
_cell_angle_alpha   81.797
_cell_angle_beta   81.797
_cell_angle_gamma   100.520
_symmetry_Int_Tables_number   1
_cell_volume   121.081
_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  0.890  0.110  0.000  1.0
  P  P1  1  0.733  0.663  0.588  1.0
  P  P2  1  0.337  0.267  0.412  1.0
  O  O3  1  0.453  0.547  0.500  1.0
  O  O4  1  0.150  0.330  0.197  1.0
  O  O5  1  0.566  0.159  0.266  1.0
  O  O6  1  0.670  0.850  0.803  1.0
  O  O7  1  0.841  0.434  0.734  1.0
  O  O8  1  0.915  0.802  0.298  1.0
  O  O9  1  0.198  0.085  0.702  1.0
[/CIF]
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The crystal structure described by FeP2O7 crystallizes in the monoclinic C2 space group. Fe(1) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(4) 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 three equivalent Fe(1)O6 octahedra and  a cornercorner with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 15-49°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a bent 120 degrees geometry to two equivalent P(1) atoms. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to one Fe(1) and one P(1) atom. In the third O site, O(3) is bonded in a linear geometry to one Fe(1) and one P(1) atom. In the fourth O site, O(4) is bonded in a distorted bent 120 degrees geometry to one Fe(1) and one P(1) atom. is represented by the CIF file [CIF]
data_FeP2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.236
_cell_length_b   5.236
_cell_length_c   4.608
_cell_angle_alpha   81.797
_cell_angle_beta   81.797
_cell_angle_gamma   100.520
_symmetry_Int_Tables_number   1
_cell_volume   121.081
_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  0.890  0.110  0.000  1.0
  P  P1  1  0.733  0.663  0.588  1.0
  P  P2  1  0.337  0.267  0.412  1.0
  O  O3  1  0.453  0.547  0.500  1.0
  O  O4  1  0.150  0.330  0.197  1.0
  O  O5  1  0.566  0.159  0.266  1.0
  O  O6  1  0.670  0.850  0.803  1.0
  O  O7  1  0.841  0.434  0.734  1.0
  O  O8  1  0.915  0.802  0.298  1.0
  O  O9  1  0.198  0.085  0.702  1.0
[/CIF]
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