The material described by Li2FeP2O7 crystallizes in the orthorhombic Imma space group. Li(1) is bonded to two equivalent O(2) and two equivalent O(3) atoms to form distorted LiO4 trigonal pyramids that share corners with four equivalent P(1)O4 tetrahedra and corners with two equivalent Li(1)O4 trigonal pyramids. Fe(1) is bonded in a square co-planar geometry to four equivalent O(3) atoms. P(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form PO4 tetrahedra that share  a cornercorner with one P(1)O4 tetrahedra and corners with four equivalent Li(1)O4 trigonal pyramids. There are three 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 trigonal planar geometry to two equivalent Li(1) and one P(1) 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. is represented by the CIF card [CIF]
data_Li2FeP2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.933
_cell_length_b   7.008
_cell_length_c   8.199
_cell_angle_alpha   115.292
_cell_angle_beta   115.014
_cell_angle_gamma   89.994
_symmetry_Int_Tables_number   1
_cell_volume   318.415
_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  1.000  1.000  1.000  1.0
  Fe  Fe1  1  0.500  0.000  0.000  1.0
  Li  Li2  1  0.232  0.232  0.464  1.0
  Li  Li3  1  0.268  0.768  0.536  1.0
  Li  Li4  1  0.768  0.768  0.536  1.0
  Li  Li5  1  0.732  0.232  0.464  1.0
  O  O6  1  0.250  0.419  1.000  1.0
  O  O7  1  0.750  0.581  0.000  1.0
  O  O8  1  0.558  0.344  0.616  1.0
  O  O9  1  0.058  0.273  0.616  1.0
  O  O10  1  0.942  0.728  0.384  1.0
  O  O11  1  0.442  0.656  0.384  1.0
  O  O12  1  0.179  0.298  0.225  1.0
  O  O13  1  0.046  0.928  0.225  1.0
  O  O14  1  0.321  0.072  0.775  1.0
  O  O15  1  0.454  0.702  0.775  1.0
  O  O16  1  0.679  0.928  0.226  1.0
  O  O17  1  0.546  0.298  0.226  1.0
  O  O18  1  0.954  0.072  0.774  1.0
  O  O19  1  0.821  0.702  0.774  1.0
  P  P20  1  0.140  0.201  0.779  1.0
  P  P21  1  0.639  0.578  0.779  1.0
  P  P22  1  0.360  0.422  0.221  1.0
  P  P23  1  0.860  0.799  0.221  1.0
[/CIF]
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The material described by Li2FeP2O7 crystallizes in the orthorhombic Imma space group. Li(1) is bonded to two equivalent O(2) and two equivalent O(3) atoms to form distorted LiO4 trigonal pyramids that share corners with four equivalent P(1)O4 tetrahedra and corners with two equivalent Li(1)O4 trigonal pyramids. Fe(1) is bonded in a square co-planar geometry to four equivalent O(3) atoms. P(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form PO4 tetrahedra that share  a cornercorner with one P(1)O4 tetrahedra and corners with four equivalent Li(1)O4 trigonal pyramids. There are three 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 trigonal planar geometry to two equivalent Li(1) and one P(1) 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. is represented by the CIF card [CIF]
data_Li2FeP2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.933
_cell_length_b   7.008
_cell_length_c   8.199
_cell_angle_alpha   115.292
_cell_angle_beta   115.014
_cell_angle_gamma   89.994
_symmetry_Int_Tables_number   1
_cell_volume   318.415
_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  1.000  1.000  1.000  1.0
  Fe  Fe1  1  0.500  0.000  0.000  1.0
  Li  Li2  1  0.232  0.232  0.464  1.0
  Li  Li3  1  0.268  0.768  0.536  1.0
  Li  Li4  1  0.768  0.768  0.536  1.0
  Li  Li5  1  0.732  0.232  0.464  1.0
  O  O6  1  0.250  0.419  1.000  1.0
  O  O7  1  0.750  0.581  0.000  1.0
  O  O8  1  0.558  0.344  0.616  1.0
  O  O9  1  0.058  0.273  0.616  1.0
  O  O10  1  0.942  0.728  0.384  1.0
  O  O11  1  0.442  0.656  0.384  1.0
  O  O12  1  0.179  0.298  0.225  1.0
  O  O13  1  0.046  0.928  0.225  1.0
  O  O14  1  0.321  0.072  0.775  1.0
  O  O15  1  0.454  0.702  0.775  1.0
  O  O16  1  0.679  0.928  0.226  1.0
  O  O17  1  0.546  0.298  0.226  1.0
  O  O18  1  0.954  0.072  0.774  1.0
  O  O19  1  0.821  0.702  0.774  1.0
  P  P20  1  0.140  0.201  0.779  1.0
  P  P21  1  0.639  0.578  0.779  1.0
  P  P22  1  0.360  0.422  0.221  1.0
  P  P23  1  0.860  0.799  0.221  1.0
[/CIF]
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