The compound described by Li2Fe5(Si2O7)2 crystallizes in the triclinic P-1 space group. Li(1) is bonded in a 3-coordinate geometry to one Fe(3), one O(1), one O(4), and one O(5) atom. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a 2-coordinate geometry to two equivalent O(2) and two equivalent O(5) atoms. In the second Fe site, Fe(2) is bonded in a 4-coordinate geometry to one O(1), one O(2), one O(5), and one O(7) atom. In the third Fe site, Fe(3) is bonded in a 7-coordinate geometry to one Li(1), one O(2), one O(3), one O(4), one O(7), and two equivalent O(6) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a 4-coordinate geometry to one O(2), one O(3), one O(4), and one O(7) atom. In the second Si site, Si(2) is bonded in a 2-coordinate geometry to one O(1) and one O(6) atom. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Li(1), one Fe(2), and one Si(2) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Fe(1), one Fe(2), one Fe(3), and one Si(1) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one Fe(3) and one Si(1) atom. In the fourth O site, O(4) is bonded in a 1-coordinate geometry to one Li(1), one Fe(3), and one Si(1) atom. In the fifth O site, O(5) is bonded in a distorted water-like geometry to one Li(1), one Fe(1), and one Fe(2) atom. In the sixth O site, O(6) is bonded in a 1-coordinate geometry to two equivalent Fe(3) and one Si(2) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Fe(2), one Fe(3), and one Si(1) atom. is represented by the CIF file [CIF]
data_Li2Fe5(Si2O7)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.644
_cell_length_b   8.120
_cell_length_c   5.546
_cell_angle_alpha   91.685
_cell_angle_beta   104.176
_cell_angle_gamma   114.869
_symmetry_Int_Tables_number   1
_cell_volume   299.319
_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
  Li  Li0  1  0.454  0.231  0.101  1.0
  Li  Li1  1  0.546  0.769  0.899  1.0
  Fe  Fe2  1  0.000  0.000  0.000  1.0
  Fe  Fe3  1  0.810  0.074  0.391  1.0
  Fe  Fe4  1  0.705  0.638  0.580  1.0
  Fe  Fe5  1  0.295  0.362  0.420  1.0
  Fe  Fe6  1  0.190  0.926  0.609  1.0
  Si  Si7  1  0.863  0.499  0.224  1.0
  Si  Si8  1  0.391  0.789  0.207  1.0
  Si  Si9  1  0.609  0.211  0.793  1.0
  Si  Si10  1  0.137  0.501  0.776  1.0
  O  O11  1  0.569  0.885  0.180  1.0
  O  O12  1  0.960  0.793  0.340  1.0
  O  O13  1  0.277  0.527  0.017  1.0
  O  O14  1  0.737  0.404  0.324  1.0
  O  O15  1  0.268  0.021  0.184  1.0
  O  O16  1  0.439  0.692  0.407  1.0
  O  O17  1  0.018  0.314  0.226  1.0
  O  O18  1  0.982  0.686  0.774  1.0
  O  O19  1  0.561  0.308  0.593  1.0
  O  O20  1  0.732  0.979  0.816  1.0
  O  O21  1  0.263  0.596  0.676  1.0
  O  O22  1  0.723  0.473  0.983  1.0
  O  O23  1  0.040  0.207  0.660  1.0
  O  O24  1  0.431  0.115  0.820  1.0
[/CIF]
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The compound described by Li2Fe5(Si2O7)2 crystallizes in the triclinic P-1 space group. Li(1) is bonded in a 3-coordinate geometry to one Fe(3), one O(1), one O(4), and one O(5) atom. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a 2-coordinate geometry to two equivalent O(2) and two equivalent O(5) atoms. In the second Fe site, Fe(2) is bonded in a 4-coordinate geometry to one O(1), one O(2), one O(5), and one O(7) atom. In the third Fe site, Fe(3) is bonded in a 7-coordinate geometry to one Li(1), one O(2), one O(3), one O(4), one O(7), and two equivalent O(6) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a 4-coordinate geometry to one O(2), one O(3), one O(4), and one O(7) atom. In the second Si site, Si(2) is bonded in a 2-coordinate geometry to one O(1) and one O(6) atom. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Li(1), one Fe(2), and one Si(2) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Fe(1), one Fe(2), one Fe(3), and one Si(1) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one Fe(3) and one Si(1) atom. In the fourth O site, O(4) is bonded in a 1-coordinate geometry to one Li(1), one Fe(3), and one Si(1) atom. In the fifth O site, O(5) is bonded in a distorted water-like geometry to one Li(1), one Fe(1), and one Fe(2) atom. In the sixth O site, O(6) is bonded in a 1-coordinate geometry to two equivalent Fe(3) and one Si(2) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Fe(2), one Fe(3), and one Si(1) atom. is represented by the CIF file [CIF]
data_Li2Fe5(Si2O7)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.644
_cell_length_b   8.120
_cell_length_c   5.546
_cell_angle_alpha   91.685
_cell_angle_beta   104.176
_cell_angle_gamma   114.869
_symmetry_Int_Tables_number   1
_cell_volume   299.319
_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
  Li  Li0  1  0.454  0.231  0.101  1.0
  Li  Li1  1  0.546  0.769  0.899  1.0
  Fe  Fe2  1  0.000  0.000  0.000  1.0
  Fe  Fe3  1  0.810  0.074  0.391  1.0
  Fe  Fe4  1  0.705  0.638  0.580  1.0
  Fe  Fe5  1  0.295  0.362  0.420  1.0
  Fe  Fe6  1  0.190  0.926  0.609  1.0
  Si  Si7  1  0.863  0.499  0.224  1.0
  Si  Si8  1  0.391  0.789  0.207  1.0
  Si  Si9  1  0.609  0.211  0.793  1.0
  Si  Si10  1  0.137  0.501  0.776  1.0
  O  O11  1  0.569  0.885  0.180  1.0
  O  O12  1  0.960  0.793  0.340  1.0
  O  O13  1  0.277  0.527  0.017  1.0
  O  O14  1  0.737  0.404  0.324  1.0
  O  O15  1  0.268  0.021  0.184  1.0
  O  O16  1  0.439  0.692  0.407  1.0
  O  O17  1  0.018  0.314  0.226  1.0
  O  O18  1  0.982  0.686  0.774  1.0
  O  O19  1  0.561  0.308  0.593  1.0
  O  O20  1  0.732  0.979  0.816  1.0
  O  O21  1  0.263  0.596  0.676  1.0
  O  O22  1  0.723  0.473  0.983  1.0
  O  O23  1  0.040  0.207  0.660  1.0
  O  O24  1  0.431  0.115  0.820  1.0
[/CIF]
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