The structure described by LiFeP2O7 crystallizes in the monoclinic Cc space group. Li(1) is bonded to one O(3), one O(5), one O(6), and one O(7) atom to form LiO4 tetrahedra that share  a cornercorner with one P(2)O4 tetrahedra and corners with three equivalent P(1)O4 tetrahedra. Fe(1) is bonded in a rectangular see-saw-like geometry to one O(1), one O(3), one O(4), and one O(7) atom. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(2), one O(3), one O(5), and one O(7) atom to form PO4 tetrahedra that share  a cornercorner with one P(2)O4 tetrahedra and corners with three equivalent Li(1)O4 tetrahedra. In the second P site, P(2) is bonded to one O(1), one O(2), one O(4), and one O(6) atom to form PO4 tetrahedra that share  a cornercorner with one Li(1)O4 tetrahedra and  a cornercorner with one P(1)O4 tetrahedra. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 150 degrees geometry to one Fe(1) and one P(2) atom. In the second O site, O(2) is bonded in a bent 120 degrees geometry to one P(1) and one P(2) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Li(1), one Fe(1), and one P(1) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one Fe(1) and one P(2) atom. In the fifth O site, O(5) is bonded in a distorted bent 120 degrees geometry to one Li(1) and one P(1) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Li(1) and one P(2) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Li(1), one Fe(1), and one P(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_LiFeP2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.220
_cell_length_b   8.220
_cell_length_c   8.812
_cell_angle_alpha   68.559
_cell_angle_beta   68.559
_cell_angle_gamma   35.374
_symmetry_Int_Tables_number   1
_cell_volume   318.334
_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
  Li  Li0  1  0.141  0.466  0.549  1.0
  Li  Li1  1  0.466  0.141  0.049  1.0
  Fe  Fe2  1  0.510  0.500  0.503  1.0
  Fe  Fe3  1  0.500  0.510  0.003  1.0
  P  P4  1  0.770  0.037  0.313  1.0
  P  P5  1  0.970  0.234  0.188  1.0
  P  P6  1  0.234  0.970  0.688  1.0
  P  P7  1  0.037  0.770  0.813  1.0
  O  O8  1  0.377  0.815  0.844  1.0
  O  O9  1  0.036  0.968  0.252  1.0
  O  O10  1  0.254  0.564  0.936  1.0
  O  O11  1  0.425  0.764  0.561  1.0
  O  O12  1  0.764  0.425  0.061  1.0
  O  O13  1  0.968  0.036  0.752  1.0
  O  O14  1  0.895  0.763  0.382  1.0
  O  O15  1  0.815  0.377  0.344  1.0
  O  O16  1  0.763  0.895  0.882  1.0
  O  O17  1  0.111  0.246  0.626  1.0
  O  O18  1  0.564  0.254  0.436  1.0
  O  O19  1  0.619  0.190  0.157  1.0
  O  O20  1  0.246  0.111  0.126  1.0
  O  O21  1  0.190  0.619  0.657  1.0
[/CIF]
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The structure described by LiFeP2O7 crystallizes in the monoclinic Cc space group. Li(1) is bonded to one O(3), one O(5), one O(6), and one O(7) atom to form LiO4 tetrahedra that share  a cornercorner with one P(2)O4 tetrahedra and corners with three equivalent P(1)O4 tetrahedra. Fe(1) is bonded in a rectangular see-saw-like geometry to one O(1), one O(3), one O(4), and one O(7) atom. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(2), one O(3), one O(5), and one O(7) atom to form PO4 tetrahedra that share  a cornercorner with one P(2)O4 tetrahedra and corners with three equivalent Li(1)O4 tetrahedra. In the second P site, P(2) is bonded to one O(1), one O(2), one O(4), and one O(6) atom to form PO4 tetrahedra that share  a cornercorner with one Li(1)O4 tetrahedra and  a cornercorner with one P(1)O4 tetrahedra. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 150 degrees geometry to one Fe(1) and one P(2) atom. In the second O site, O(2) is bonded in a bent 120 degrees geometry to one P(1) and one P(2) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Li(1), one Fe(1), and one P(1) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one Fe(1) and one P(2) atom. In the fifth O site, O(5) is bonded in a distorted bent 120 degrees geometry to one Li(1) and one P(1) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Li(1) and one P(2) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Li(1), one Fe(1), and one P(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_LiFeP2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.220
_cell_length_b   8.220
_cell_length_c   8.812
_cell_angle_alpha   68.559
_cell_angle_beta   68.559
_cell_angle_gamma   35.374
_symmetry_Int_Tables_number   1
_cell_volume   318.334
_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
  Li  Li0  1  0.141  0.466  0.549  1.0
  Li  Li1  1  0.466  0.141  0.049  1.0
  Fe  Fe2  1  0.510  0.500  0.503  1.0
  Fe  Fe3  1  0.500  0.510  0.003  1.0
  P  P4  1  0.770  0.037  0.313  1.0
  P  P5  1  0.970  0.234  0.188  1.0
  P  P6  1  0.234  0.970  0.688  1.0
  P  P7  1  0.037  0.770  0.813  1.0
  O  O8  1  0.377  0.815  0.844  1.0
  O  O9  1  0.036  0.968  0.252  1.0
  O  O10  1  0.254  0.564  0.936  1.0
  O  O11  1  0.425  0.764  0.561  1.0
  O  O12  1  0.764  0.425  0.061  1.0
  O  O13  1  0.968  0.036  0.752  1.0
  O  O14  1  0.895  0.763  0.382  1.0
  O  O15  1  0.815  0.377  0.344  1.0
  O  O16  1  0.763  0.895  0.882  1.0
  O  O17  1  0.111  0.246  0.626  1.0
  O  O18  1  0.564  0.254  0.436  1.0
  O  O19  1  0.619  0.190  0.157  1.0
  O  O20  1  0.246  0.111  0.126  1.0
  O  O21  1  0.190  0.619  0.657  1.0
[/CIF]
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