The material structure described by Li2Fe2Si2O7 crystallizes in the orthorhombic Ama2 space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded in a 4-coordinate geometry to two equivalent O(1) and two equivalent O(3) atoms. In the second Li site, Li(2) is bonded in a 4-coordinate geometry to two equivalent O(1) and two equivalent O(3) atoms. Fe(1) is bonded in a rectangular see-saw-like geometry to one O(1), one O(3), and two equivalent O(4) atoms. Si(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form corner-sharing SiO4 tetrahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Li(1), one Li(2), one Fe(1), and one Si(1) atom to form a mixture of distorted edge and corner-sharing OLi2FeSi tetrahedra. In the second O site, O(2) is bonded in a bent 120 degrees geometry to two equivalent Si(1) atoms. In the third O site, O(3) is bonded to one Li(1), one Li(2), one Fe(1), and one Si(1) atom to form a mixture of distorted edge and corner-sharing OLi2FeSi trigonal pyramids. In the fourth O site, O(4) is bonded in a trigonal planar geometry to two equivalent Fe(1) and one Si(1) atom. is represented by the CIF card [CIF]
data_Li2Fe2Si2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.408
_cell_length_b   5.408
_cell_length_c   13.332
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   124.605
_symmetry_Int_Tables_number   1
_cell_volume   320.954
_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  0.015  0.015  0.500  1.0
  Li  Li1  1  0.015  0.015  0.000  1.0
  Li  Li2  1  0.978  0.001  0.250  1.0
  Li  Li3  1  0.001  0.978  0.750  1.0
  Fe  Fe4  1  0.773  0.344  0.914  1.0
  Fe  Fe5  1  0.773  0.344  0.586  1.0
  Fe  Fe6  1  0.344  0.773  0.086  1.0
  Fe  Fe7  1  0.344  0.773  0.414  1.0
  Si  Si8  1  0.663  0.435  0.139  1.0
  Si  Si9  1  0.663  0.435  0.361  1.0
  Si  Si10  1  0.435  0.663  0.861  1.0
  Si  Si11  1  0.435  0.663  0.639  1.0
  O  O12  1  0.314  0.129  0.379  1.0
  O  O13  1  0.314  0.129  0.121  1.0
  O  O14  1  0.796  0.428  0.250  1.0
  O  O15  1  0.747  0.671  0.633  1.0
  O  O16  1  0.747  0.671  0.867  1.0
  O  O17  1  0.900  0.447  0.441  1.0
  O  O18  1  0.900  0.447  0.059  1.0
  O  O19  1  0.129  0.314  0.621  1.0
  O  O20  1  0.129  0.314  0.879  1.0
  O  O21  1  0.428  0.796  0.750  1.0
  O  O22  1  0.671  0.747  0.367  1.0
  O  O23  1  0.671  0.747  0.133  1.0
  O  O24  1  0.447  0.900  0.941  1.0
  O  O25  1  0.447  0.900  0.559  1.0
[/CIF]
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The material structure described by Li2Fe2Si2O7 crystallizes in the orthorhombic Ama2 space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded in a 4-coordinate geometry to two equivalent O(1) and two equivalent O(3) atoms. In the second Li site, Li(2) is bonded in a 4-coordinate geometry to two equivalent O(1) and two equivalent O(3) atoms. Fe(1) is bonded in a rectangular see-saw-like geometry to one O(1), one O(3), and two equivalent O(4) atoms. Si(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form corner-sharing SiO4 tetrahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Li(1), one Li(2), one Fe(1), and one Si(1) atom to form a mixture of distorted edge and corner-sharing OLi2FeSi tetrahedra. In the second O site, O(2) is bonded in a bent 120 degrees geometry to two equivalent Si(1) atoms. In the third O site, O(3) is bonded to one Li(1), one Li(2), one Fe(1), and one Si(1) atom to form a mixture of distorted edge and corner-sharing OLi2FeSi trigonal pyramids. In the fourth O site, O(4) is bonded in a trigonal planar geometry to two equivalent Fe(1) and one Si(1) atom. is represented by the CIF card [CIF]
data_Li2Fe2Si2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.408
_cell_length_b   5.408
_cell_length_c   13.332
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   124.605
_symmetry_Int_Tables_number   1
_cell_volume   320.954
_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  0.015  0.015  0.500  1.0
  Li  Li1  1  0.015  0.015  0.000  1.0
  Li  Li2  1  0.978  0.001  0.250  1.0
  Li  Li3  1  0.001  0.978  0.750  1.0
  Fe  Fe4  1  0.773  0.344  0.914  1.0
  Fe  Fe5  1  0.773  0.344  0.586  1.0
  Fe  Fe6  1  0.344  0.773  0.086  1.0
  Fe  Fe7  1  0.344  0.773  0.414  1.0
  Si  Si8  1  0.663  0.435  0.139  1.0
  Si  Si9  1  0.663  0.435  0.361  1.0
  Si  Si10  1  0.435  0.663  0.861  1.0
  Si  Si11  1  0.435  0.663  0.639  1.0
  O  O12  1  0.314  0.129  0.379  1.0
  O  O13  1  0.314  0.129  0.121  1.0
  O  O14  1  0.796  0.428  0.250  1.0
  O  O15  1  0.747  0.671  0.633  1.0
  O  O16  1  0.747  0.671  0.867  1.0
  O  O17  1  0.900  0.447  0.441  1.0
  O  O18  1  0.900  0.447  0.059  1.0
  O  O19  1  0.129  0.314  0.621  1.0
  O  O20  1  0.129  0.314  0.879  1.0
  O  O21  1  0.428  0.796  0.750  1.0
  O  O22  1  0.671  0.747  0.367  1.0
  O  O23  1  0.671  0.747  0.133  1.0
  O  O24  1  0.447  0.900  0.941  1.0
  O  O25  1  0.447  0.900  0.559  1.0
[/CIF]
.