The crystal structure described by Li2FeP2O7 crystallizes in the triclinic P-1 space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded in a 2-coordinate geometry to one O(4) and one O(7) atom. In the second Li site, Li(2) is bonded in a 5-coordinate geometry to one P(2), one O(1), one O(2), one O(3), and one O(4) atom. Fe(1) is bonded in a 4-coordinate geometry to one O(1), one O(2), one O(3), and one O(6) atom. There are two inequivalent P sites. In the first P site, P(1) is bonded in a 3-coordinate geometry to one O(1), one O(2), one O(6), and one O(7) atom. In the second P site, P(2) is bonded in a 3-coordinate geometry to one Li(2), one O(3), one O(4), one O(5), and one O(7) atom. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted water-like geometry to one Li(2), one Fe(1), and one P(1) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Li(2), one Fe(1), and one P(1) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one Li(2), one Fe(1), and one P(2) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Li(1), one Li(2), and one P(2) atom. In the fifth O site, O(5) is bonded in a single-bond geometry to one P(2) atom. In the sixth O site, O(6) is bonded in a bent 120 degrees geometry to one Fe(1) and one P(1) atom. In the seventh O site, O(7) is bonded in a distorted single-bond geometry to one Li(1), one P(1), and one P(2) atom. is represented by the CIF card [CIF]
data_Li2FeP2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.341
_cell_length_b   6.563
_cell_length_c   8.915
_cell_angle_alpha   109.758
_cell_angle_beta   94.772
_cell_angle_gamma   107.765
_symmetry_Int_Tables_number   1
_cell_volume   274.001
_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  0.105  0.756  0.002  1.0
  Li  Li1  1  0.578  0.462  0.751  1.0
  Li  Li2  1  0.422  0.538  0.249  1.0
  Li  Li3  1  0.895  0.244  0.998  1.0
  Fe  Fe4  1  0.744  0.240  0.365  1.0
  Fe  Fe5  1  0.256  0.760  0.635  1.0
  P  P6  1  0.846  0.758  0.391  1.0
  P  P7  1  0.698  0.817  0.884  1.0
  P  P8  1  0.302  0.183  0.116  1.0
  P  P9  1  0.154  0.242  0.609  1.0
  O  O10  1  0.729  0.558  0.333  1.0
  O  O11  1  0.646  0.886  0.417  1.0
  O  O12  1  0.436  0.724  0.842  1.0
  O  O13  1  0.102  0.309  0.154  1.0
  O  O14  1  0.362  0.171  0.945  1.0
  O  O15  1  0.075  0.308  0.463  1.0
  O  O16  1  0.868  0.080  0.766  1.0
  O  O17  1  0.132  0.920  0.234  1.0
  O  O18  1  0.925  0.692  0.537  1.0
  O  O19  1  0.638  0.829  0.055  1.0
  O  O20  1  0.898  0.691  0.846  1.0
  O  O21  1  0.564  0.276  0.158  1.0
  O  O22  1  0.354  0.114  0.583  1.0
  O  O23  1  0.271  0.442  0.667  1.0
[/CIF]
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The crystal structure described by Li2FeP2O7 crystallizes in the triclinic P-1 space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded in a 2-coordinate geometry to one O(4) and one O(7) atom. In the second Li site, Li(2) is bonded in a 5-coordinate geometry to one P(2), one O(1), one O(2), one O(3), and one O(4) atom. Fe(1) is bonded in a 4-coordinate geometry to one O(1), one O(2), one O(3), and one O(6) atom. There are two inequivalent P sites. In the first P site, P(1) is bonded in a 3-coordinate geometry to one O(1), one O(2), one O(6), and one O(7) atom. In the second P site, P(2) is bonded in a 3-coordinate geometry to one Li(2), one O(3), one O(4), one O(5), and one O(7) atom. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted water-like geometry to one Li(2), one Fe(1), and one P(1) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Li(2), one Fe(1), and one P(1) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one Li(2), one Fe(1), and one P(2) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Li(1), one Li(2), and one P(2) atom. In the fifth O site, O(5) is bonded in a single-bond geometry to one P(2) atom. In the sixth O site, O(6) is bonded in a bent 120 degrees geometry to one Fe(1) and one P(1) atom. In the seventh O site, O(7) is bonded in a distorted single-bond geometry to one Li(1), one P(1), and one P(2) atom. is represented by the CIF card [CIF]
data_Li2FeP2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.341
_cell_length_b   6.563
_cell_length_c   8.915
_cell_angle_alpha   109.758
_cell_angle_beta   94.772
_cell_angle_gamma   107.765
_symmetry_Int_Tables_number   1
_cell_volume   274.001
_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  0.105  0.756  0.002  1.0
  Li  Li1  1  0.578  0.462  0.751  1.0
  Li  Li2  1  0.422  0.538  0.249  1.0
  Li  Li3  1  0.895  0.244  0.998  1.0
  Fe  Fe4  1  0.744  0.240  0.365  1.0
  Fe  Fe5  1  0.256  0.760  0.635  1.0
  P  P6  1  0.846  0.758  0.391  1.0
  P  P7  1  0.698  0.817  0.884  1.0
  P  P8  1  0.302  0.183  0.116  1.0
  P  P9  1  0.154  0.242  0.609  1.0
  O  O10  1  0.729  0.558  0.333  1.0
  O  O11  1  0.646  0.886  0.417  1.0
  O  O12  1  0.436  0.724  0.842  1.0
  O  O13  1  0.102  0.309  0.154  1.0
  O  O14  1  0.362  0.171  0.945  1.0
  O  O15  1  0.075  0.308  0.463  1.0
  O  O16  1  0.868  0.080  0.766  1.0
  O  O17  1  0.132  0.920  0.234  1.0
  O  O18  1  0.925  0.692  0.537  1.0
  O  O19  1  0.638  0.829  0.055  1.0
  O  O20  1  0.898  0.691  0.846  1.0
  O  O21  1  0.564  0.276  0.158  1.0
  O  O22  1  0.354  0.114  0.583  1.0
  O  O23  1  0.271  0.442  0.667  1.0
[/CIF]
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