The material described by Li4Fe2SiO7 crystallizes in the triclinic P-1 space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded to one O(2), one O(4), two equivalent O(1), and two equivalent O(3) atoms to form LiO6 octahedra that share  a cornercorner with one Li(1)O6 octahedra,  a cornercorner with one Si(1)O6 octahedra, corners with two equivalent Fe(1)O6 octahedra, corners with three equivalent Li(2)O5 square pyramids, edges with two equivalent Li(1)O6 octahedra, edges with two equivalent Si(1)O6 octahedra, edges with four equivalent Fe(1)O6 octahedra, and edges with three equivalent Li(2)O5 square pyramids. The corner-sharing octahedral tilt angles range from 0-22°. In the second Li site, Li(2) is bonded to one O(2), one O(3), one O(4), and two equivalent O(1) atoms to form distorted LiO5 square pyramids that share corners with three equivalent Li(1)O6 octahedra, corners with four equivalent Fe(1)O6 octahedra,  a cornercorner with one Li(2)O5 square pyramid, edges with two equivalent Fe(1)O6 octahedra, edges with two equivalent Si(1)O6 octahedra, edges with three equivalent Li(1)O6 octahedra, and  an edgeedge with one Li(2)O5 square pyramid. The corner-sharing octahedral tilt angles range from 12-87°. Fe(1) is bonded to one O(1), one O(2), two equivalent O(3), and two equivalent O(4) atoms to form FeO6 octahedra that share  a cornercorner with one Fe(1)O6 octahedra,  a cornercorner with one Si(1)O6 octahedra, corners with two equivalent Li(1)O6 octahedra, corners with four equivalent Li(2)O5 square pyramids, edges with two equivalent Fe(1)O6 octahedra, edges with two equivalent Si(1)O6 octahedra, edges with four equivalent Li(1)O6 octahedra, and edges with two equivalent Li(2)O5 square pyramids. The corner-sharing octahedral tilt angles range from 0-22°. Si(1) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form SiO6 octahedra that share corners with two equivalent Li(1)O6 octahedra, corners with two equivalent Fe(1)O6 octahedra, edges with four equivalent Li(1)O6 octahedra, edges with four equivalent Fe(1)O6 octahedra, and edges with four equivalent Li(2)O5 square pyramids. The corner-sharing octahedral tilt angles range from 5-8°. There are four inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Li(1), two equivalent Li(2), one Fe(1), and one Si(1) atom to form OLi4FeSi octahedra that share  a cornercorner with one O(2)Li4Fe2 octahedra,  a cornercorner with one O(1)Li4FeSi octahedra, corners with two equivalent O(3)Li3Fe2Si octahedra, corners with two equivalent O(4)Li2Fe2Si square pyramids, edges with two equivalent O(2)Li4Fe2 octahedra, edges with two equivalent O(1)Li4FeSi octahedra, edges with four equivalent O(3)Li3Fe2Si octahedra, and edges with three equivalent O(4)Li2Fe2Si square pyramids. The corner-sharing octahedral tilt angles range from 0-16°. In the second O site, O(2) is bonded to two equivalent Li(1), two equivalent Li(2), and two equivalent Fe(1) atoms to form OLi4Fe2 octahedra that share corners with two equivalent O(3)Li3Fe2Si octahedra, corners with two equivalent O(1)Li4FeSi octahedra, corners with four equivalent O(4)Li2Fe2Si square pyramids, edges with four equivalent O(3)Li3Fe2Si octahedra, edges with four equivalent O(1)Li4FeSi octahedra, and edges with two equivalent O(4)Li2Fe2Si square pyramids. The corner-sharing octahedral tilt angles range from 2-16°. In the third O site, O(3) is bonded to one Li(2), two equivalent Li(1), two equivalent Fe(1), and one Si(1) atom to form OLi3Fe2Si octahedra that share  a cornercorner with one O(3)Li3Fe2Si octahedra,  a cornercorner with one O(2)Li4Fe2 octahedra, corners with two equivalent O(1)Li4FeSi octahedra, corners with three equivalent O(4)Li2Fe2Si square pyramids, edges with two equivalent O(3)Li3Fe2Si octahedra, edges with two equivalent O(2)Li4Fe2 octahedra, edges with four equivalent O(1)Li4FeSi octahedra, and edges with three equivalent O(4)Li2Fe2Si square pyramids. The corner-sharing octahedral tilt angles range from 0-13°. In the fourth O site, O(4) is bonded to one Li(1), one Li(2), two equivalent Fe(1), and one Si(1) atom to form distorted OLi2Fe2Si square pyramids that share corners with two equivalent O(2)Li4Fe2 octahedra, corners with two equivalent O(1)Li4FeSi octahedra, corners with three equivalent O(3)Li3Fe2Si octahedra,  a cornercorner with one O(4)Li2Fe2Si square pyramid,  an edgeedge with one O(2)Li4Fe2 octahedra, edges with three equivalent O(3)Li3Fe2Si octahedra, edges with three equivalent O(1)Li4FeSi octahedra, and  an edgeedge with one O(4)Li2Fe2Si square pyramid. The corner-sharing octahedral tilt angles range from 4-88°. is represented by the CIF file [CIF]
data_Li4Fe2SiO7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.983
_cell_length_b   5.039
_cell_length_c   5.120
_cell_angle_alpha   95.368
_cell_angle_beta   100.490
_cell_angle_gamma   101.817
_symmetry_Int_Tables_number   1
_cell_volume   122.581
_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  0.075  0.651  0.794  1.0
  Li  Li1  1  0.358  0.245  0.950  1.0
  Li  Li2  1  0.642  0.755  0.050  1.0
  Li  Li3  1  0.925  0.349  0.206  1.0
  Fe  Fe4  1  0.199  0.918  0.341  1.0
  Fe  Fe5  1  0.801  0.082  0.659  1.0
  Si  Si6  1  0.500  0.500  0.500  1.0
  O  O7  1  0.306  0.582  0.194  1.0
  O  O8  1  0.000  0.000  0.000  1.0
  O  O9  1  0.169  0.276  0.561  1.0
  O  O10  1  0.437  0.802  0.677  1.0
  O  O11  1  0.563  0.198  0.323  1.0
  O  O12  1  0.831  0.724  0.439  1.0
  O  O13  1  0.694  0.418  0.806  1.0
[/CIF]
.
The material described by Li4Fe2SiO7 crystallizes in the triclinic P-1 space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded to one O(2), one O(4), two equivalent O(1), and two equivalent O(3) atoms to form LiO6 octahedra that share  a cornercorner with one Li(1)O6 octahedra,  a cornercorner with one Si(1)O6 octahedra, corners with two equivalent Fe(1)O6 octahedra, corners with three equivalent Li(2)O5 square pyramids, edges with two equivalent Li(1)O6 octahedra, edges with two equivalent Si(1)O6 octahedra, edges with four equivalent Fe(1)O6 octahedra, and edges with three equivalent Li(2)O5 square pyramids. The corner-sharing octahedral tilt angles range from 0-22°. In the second Li site, Li(2) is bonded to one O(2), one O(3), one O(4), and two equivalent O(1) atoms to form distorted LiO5 square pyramids that share corners with three equivalent Li(1)O6 octahedra, corners with four equivalent Fe(1)O6 octahedra,  a cornercorner with one Li(2)O5 square pyramid, edges with two equivalent Fe(1)O6 octahedra, edges with two equivalent Si(1)O6 octahedra, edges with three equivalent Li(1)O6 octahedra, and  an edgeedge with one Li(2)O5 square pyramid. The corner-sharing octahedral tilt angles range from 12-87°. Fe(1) is bonded to one O(1), one O(2), two equivalent O(3), and two equivalent O(4) atoms to form FeO6 octahedra that share  a cornercorner with one Fe(1)O6 octahedra,  a cornercorner with one Si(1)O6 octahedra, corners with two equivalent Li(1)O6 octahedra, corners with four equivalent Li(2)O5 square pyramids, edges with two equivalent Fe(1)O6 octahedra, edges with two equivalent Si(1)O6 octahedra, edges with four equivalent Li(1)O6 octahedra, and edges with two equivalent Li(2)O5 square pyramids. The corner-sharing octahedral tilt angles range from 0-22°. Si(1) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form SiO6 octahedra that share corners with two equivalent Li(1)O6 octahedra, corners with two equivalent Fe(1)O6 octahedra, edges with four equivalent Li(1)O6 octahedra, edges with four equivalent Fe(1)O6 octahedra, and edges with four equivalent Li(2)O5 square pyramids. The corner-sharing octahedral tilt angles range from 5-8°. There are four inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Li(1), two equivalent Li(2), one Fe(1), and one Si(1) atom to form OLi4FeSi octahedra that share  a cornercorner with one O(2)Li4Fe2 octahedra,  a cornercorner with one O(1)Li4FeSi octahedra, corners with two equivalent O(3)Li3Fe2Si octahedra, corners with two equivalent O(4)Li2Fe2Si square pyramids, edges with two equivalent O(2)Li4Fe2 octahedra, edges with two equivalent O(1)Li4FeSi octahedra, edges with four equivalent O(3)Li3Fe2Si octahedra, and edges with three equivalent O(4)Li2Fe2Si square pyramids. The corner-sharing octahedral tilt angles range from 0-16°. In the second O site, O(2) is bonded to two equivalent Li(1), two equivalent Li(2), and two equivalent Fe(1) atoms to form OLi4Fe2 octahedra that share corners with two equivalent O(3)Li3Fe2Si octahedra, corners with two equivalent O(1)Li4FeSi octahedra, corners with four equivalent O(4)Li2Fe2Si square pyramids, edges with four equivalent O(3)Li3Fe2Si octahedra, edges with four equivalent O(1)Li4FeSi octahedra, and edges with two equivalent O(4)Li2Fe2Si square pyramids. The corner-sharing octahedral tilt angles range from 2-16°. In the third O site, O(3) is bonded to one Li(2), two equivalent Li(1), two equivalent Fe(1), and one Si(1) atom to form OLi3Fe2Si octahedra that share  a cornercorner with one O(3)Li3Fe2Si octahedra,  a cornercorner with one O(2)Li4Fe2 octahedra, corners with two equivalent O(1)Li4FeSi octahedra, corners with three equivalent O(4)Li2Fe2Si square pyramids, edges with two equivalent O(3)Li3Fe2Si octahedra, edges with two equivalent O(2)Li4Fe2 octahedra, edges with four equivalent O(1)Li4FeSi octahedra, and edges with three equivalent O(4)Li2Fe2Si square pyramids. The corner-sharing octahedral tilt angles range from 0-13°. In the fourth O site, O(4) is bonded to one Li(1), one Li(2), two equivalent Fe(1), and one Si(1) atom to form distorted OLi2Fe2Si square pyramids that share corners with two equivalent O(2)Li4Fe2 octahedra, corners with two equivalent O(1)Li4FeSi octahedra, corners with three equivalent O(3)Li3Fe2Si octahedra,  a cornercorner with one O(4)Li2Fe2Si square pyramid,  an edgeedge with one O(2)Li4Fe2 octahedra, edges with three equivalent O(3)Li3Fe2Si octahedra, edges with three equivalent O(1)Li4FeSi octahedra, and  an edgeedge with one O(4)Li2Fe2Si square pyramid. The corner-sharing octahedral tilt angles range from 4-88°. is represented by the CIF file [CIF]
data_Li4Fe2SiO7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.983
_cell_length_b   5.039
_cell_length_c   5.120
_cell_angle_alpha   95.368
_cell_angle_beta   100.490
_cell_angle_gamma   101.817
_symmetry_Int_Tables_number   1
_cell_volume   122.581
_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  0.075  0.651  0.794  1.0
  Li  Li1  1  0.358  0.245  0.950  1.0
  Li  Li2  1  0.642  0.755  0.050  1.0
  Li  Li3  1  0.925  0.349  0.206  1.0
  Fe  Fe4  1  0.199  0.918  0.341  1.0
  Fe  Fe5  1  0.801  0.082  0.659  1.0
  Si  Si6  1  0.500  0.500  0.500  1.0
  O  O7  1  0.306  0.582  0.194  1.0
  O  O8  1  0.000  0.000  0.000  1.0
  O  O9  1  0.169  0.276  0.561  1.0
  O  O10  1  0.437  0.802  0.677  1.0
  O  O11  1  0.563  0.198  0.323  1.0
  O  O12  1  0.831  0.724  0.439  1.0
  O  O13  1  0.694  0.418  0.806  1.0
[/CIF]
.