The crystal structure described by Li2FeSiO4 crystallizes in the monoclinic P2_1 space group. There are four inequivalent Li sites. In the first Li site, Li(1) is bonded to one O(2), one O(3), one O(6), and one O(7) atom to form distorted LiO4 tetrahedra that share corners with two equivalent Li(2)O4 tetrahedra, corners with two equivalent Li(4)O4 tetrahedra, corners with two equivalent Fe(1)O4 tetrahedra, corners with two equivalent Fe(2)O4 tetrahedra, corners with two equivalent Si(1)O4 tetrahedra, and  an edgeedge with one Si(2)O4 tetrahedra. In the second Li site, Li(2) is bonded to one O(1), one O(3), one O(5), and one O(7) atom to form LiO4 tetrahedra that share corners with two equivalent Li(1)O4 tetrahedra, corners with two equivalent Fe(1)O4 tetrahedra, corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra,  an edgeedge with one Li(3)O4 tetrahedra, and  an edgeedge with one Fe(2)O4 tetrahedra. In the third Li site, Li(3) is bonded to one O(1), one O(4), one O(5), and one O(8) atom to form distorted LiO4 tetrahedra that share corners with two equivalent Li(4)O4 tetrahedra, corners with two equivalent Fe(1)O4 tetrahedra, corners with two equivalent Fe(2)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra,  an edgeedge with one Li(2)O4 tetrahedra, and  an edgeedge with one Si(1)O4 tetrahedra. In the fourth Li site, Li(4) is bonded to one O(2), one O(4), one O(6), and one O(8) atom to form distorted LiO4 tetrahedra that share corners with two equivalent Li(1)O4 tetrahedra, corners with two equivalent Li(3)O4 tetrahedra, corners with two equivalent Fe(1)O4 tetrahedra, corners with two equivalent Fe(2)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra, and  an edgeedge with one Si(1)O4 tetrahedra. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one O(2), one O(7), and one O(8) atom to form FeO4 tetrahedra that share corners with two equivalent Li(1)O4 tetrahedra, corners with two equivalent Li(2)O4 tetrahedra, corners with two equivalent Li(3)O4 tetrahedra, corners with two equivalent Li(4)O4 tetrahedra, corners with two equivalent Si(1)O4 tetrahedra, and corners with two equivalent Si(2)O4 tetrahedra. In the second Fe site, Fe(2) is bonded to one O(3), one O(4), one O(5), and one O(6) atom to form FeO4 tetrahedra that share corners with two equivalent Li(1)O4 tetrahedra, corners with two equivalent Li(3)O4 tetrahedra, corners with two equivalent Li(4)O4 tetrahedra, corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra, and  an edgeedge with one Li(2)O4 tetrahedra. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form SiO4 tetrahedra that share corners with two equivalent Li(1)O4 tetrahedra, corners with two equivalent Li(2)O4 tetrahedra, corners with two equivalent Fe(1)O4 tetrahedra, corners with two equivalent Fe(2)O4 tetrahedra,  an edgeedge with one Li(3)O4 tetrahedra, and  an edgeedge with one Li(4)O4 tetrahedra. In the second Si site, Si(2) is bonded to one O(5), one O(6), one O(7), and one O(8) atom to form SiO4 tetrahedra that share corners with two equivalent Li(2)O4 tetrahedra, corners with two equivalent Li(3)O4 tetrahedra, corners with two equivalent Li(4)O4 tetrahedra, corners with two equivalent Fe(1)O4 tetrahedra, corners with two equivalent Fe(2)O4 tetrahedra, and  an edgeedge with one Li(1)O4 tetrahedra. There are eight inequivalent O sites. In the first O site, O(1) is bonded to one Li(2), one Li(3), one Fe(1), and one Si(1) atom to form a mixture of distorted corner and edge-sharing OLi2FeSi trigonal pyramids. In the second O site, O(2) is bonded to one Li(1), one Li(4), one Fe(1), and one Si(1) atom to form a mixture of distorted corner and edge-sharing OLi2FeSi trigonal pyramids. In the third O site, O(3) is bonded to one Li(1), one Li(2), one Fe(2), and one Si(1) atom to form a mixture of corner and edge-sharing OLi2FeSi tetrahedra. In the fourth O site, O(4) is bonded to one Li(3), one Li(4), one Fe(2), and one Si(1) atom to form a mixture of corner and edge-sharing OLi2FeSi tetrahedra. In the fifth O site, O(5) is bonded to one Li(2), one Li(3), one Fe(2), and one Si(2) atom to form a mixture of distorted corner and edge-sharing OLi2FeSi trigonal pyramids. In the sixth O site, O(6) is bonded to one Li(1), one Li(4), one Fe(2), and one Si(2) atom to form a mixture of corner and edge-sharing OLi2FeSi trigonal pyramids. In the seventh O site, O(7) is bonded to one Li(1), one Li(2), one Fe(1), and one Si(2) atom to form a mixture of distorted corner and edge-sharing OLi2FeSi tetrahedra. In the eighth O site, O(8) is bonded to one Li(3), one Li(4), one Fe(1), and one Si(2) atom to form corner-sharing OLi2FeSi tetrahedra. is represented by the CIF card [CIF]
data_Li2FeSiO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.806
_cell_length_b   5.405
_cell_length_c   6.289
_cell_angle_alpha   88.776
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   367.270
_cell_formula_units_Z   4
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  0.666  0.916  0.734  1.0
  Li  Li1  1  0.166  0.084  0.266  1.0
  Li  Li2  1  0.663  0.047  0.242  1.0
  Li  Li3  1  0.835  0.431  0.237  1.0
  Li  Li4  1  0.334  0.576  0.233  1.0
  Li  Li5  1  0.834  0.424  0.767  1.0
  Li  Li6  1  0.335  0.569  0.763  1.0
  Li  Li7  1  0.163  0.953  0.758  1.0
  Fe  Fe8  1  0.419  0.083  0.998  1.0
  Fe  Fe9  1  0.919  0.917  0.002  1.0
  Fe  Fe10  1  0.582  0.427  0.508  1.0
  Fe  Fe11  1  0.082  0.573  0.492  1.0
  Si  Si12  1  0.917  0.070  0.500  1.0
  Si  Si13  1  0.417  0.930  0.500  1.0
  Si  Si14  1  0.584  0.570  0.007  1.0
  Si  Si15  1  0.084  0.430  0.993  1.0
  O  O16  1  0.340  0.996  0.718  1.0
  O  O17  1  0.839  0.998  0.718  1.0
  O  O18  1  0.058  0.951  0.495  1.0
  O  O19  1  0.558  0.049  0.505  1.0
  O  O20  1  0.424  0.623  0.499  1.0
  O  O21  1  0.924  0.377  0.501  1.0
  O  O22  1  0.339  0.002  0.282  1.0
  O  O23  1  0.840  0.004  0.282  1.0
  O  O24  1  0.658  0.442  0.211  1.0
  O  O25  1  0.161  0.483  0.215  1.0
  O  O26  1  0.579  0.877  0.018  1.0
  O  O27  1  0.940  0.537  0.002  1.0
  O  O28  1  0.440  0.463  0.998  1.0
  O  O29  1  0.079  0.123  0.982  1.0
  O  O30  1  0.661  0.517  0.785  1.0
  O  O31  1  0.158  0.558  0.789  1.0
[/CIF]
.
The crystal structure described by Li2FeSiO4 crystallizes in the monoclinic P2_1 space group. There are four inequivalent Li sites. In the first Li site, Li(1) is bonded to one O(2), one O(3), one O(6), and one O(7) atom to form distorted LiO4 tetrahedra that share corners with two equivalent Li(2)O4 tetrahedra, corners with two equivalent Li(4)O4 tetrahedra, corners with two equivalent Fe(1)O4 tetrahedra, corners with two equivalent Fe(2)O4 tetrahedra, corners with two equivalent Si(1)O4 tetrahedra, and  an edgeedge with one Si(2)O4 tetrahedra. In the second Li site, Li(2) is bonded to one O(1), one O(3), one O(5), and one O(7) atom to form LiO4 tetrahedra that share corners with two equivalent Li(1)O4 tetrahedra, corners with two equivalent Fe(1)O4 tetrahedra, corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra,  an edgeedge with one Li(3)O4 tetrahedra, and  an edgeedge with one Fe(2)O4 tetrahedra. In the third Li site, Li(3) is bonded to one O(1), one O(4), one O(5), and one O(8) atom to form distorted LiO4 tetrahedra that share corners with two equivalent Li(4)O4 tetrahedra, corners with two equivalent Fe(1)O4 tetrahedra, corners with two equivalent Fe(2)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra,  an edgeedge with one Li(2)O4 tetrahedra, and  an edgeedge with one Si(1)O4 tetrahedra. In the fourth Li site, Li(4) is bonded to one O(2), one O(4), one O(6), and one O(8) atom to form distorted LiO4 tetrahedra that share corners with two equivalent Li(1)O4 tetrahedra, corners with two equivalent Li(3)O4 tetrahedra, corners with two equivalent Fe(1)O4 tetrahedra, corners with two equivalent Fe(2)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra, and  an edgeedge with one Si(1)O4 tetrahedra. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one O(2), one O(7), and one O(8) atom to form FeO4 tetrahedra that share corners with two equivalent Li(1)O4 tetrahedra, corners with two equivalent Li(2)O4 tetrahedra, corners with two equivalent Li(3)O4 tetrahedra, corners with two equivalent Li(4)O4 tetrahedra, corners with two equivalent Si(1)O4 tetrahedra, and corners with two equivalent Si(2)O4 tetrahedra. In the second Fe site, Fe(2) is bonded to one O(3), one O(4), one O(5), and one O(6) atom to form FeO4 tetrahedra that share corners with two equivalent Li(1)O4 tetrahedra, corners with two equivalent Li(3)O4 tetrahedra, corners with two equivalent Li(4)O4 tetrahedra, corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra, and  an edgeedge with one Li(2)O4 tetrahedra. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form SiO4 tetrahedra that share corners with two equivalent Li(1)O4 tetrahedra, corners with two equivalent Li(2)O4 tetrahedra, corners with two equivalent Fe(1)O4 tetrahedra, corners with two equivalent Fe(2)O4 tetrahedra,  an edgeedge with one Li(3)O4 tetrahedra, and  an edgeedge with one Li(4)O4 tetrahedra. In the second Si site, Si(2) is bonded to one O(5), one O(6), one O(7), and one O(8) atom to form SiO4 tetrahedra that share corners with two equivalent Li(2)O4 tetrahedra, corners with two equivalent Li(3)O4 tetrahedra, corners with two equivalent Li(4)O4 tetrahedra, corners with two equivalent Fe(1)O4 tetrahedra, corners with two equivalent Fe(2)O4 tetrahedra, and  an edgeedge with one Li(1)O4 tetrahedra. There are eight inequivalent O sites. In the first O site, O(1) is bonded to one Li(2), one Li(3), one Fe(1), and one Si(1) atom to form a mixture of distorted corner and edge-sharing OLi2FeSi trigonal pyramids. In the second O site, O(2) is bonded to one Li(1), one Li(4), one Fe(1), and one Si(1) atom to form a mixture of distorted corner and edge-sharing OLi2FeSi trigonal pyramids. In the third O site, O(3) is bonded to one Li(1), one Li(2), one Fe(2), and one Si(1) atom to form a mixture of corner and edge-sharing OLi2FeSi tetrahedra. In the fourth O site, O(4) is bonded to one Li(3), one Li(4), one Fe(2), and one Si(1) atom to form a mixture of corner and edge-sharing OLi2FeSi tetrahedra. In the fifth O site, O(5) is bonded to one Li(2), one Li(3), one Fe(2), and one Si(2) atom to form a mixture of distorted corner and edge-sharing OLi2FeSi trigonal pyramids. In the sixth O site, O(6) is bonded to one Li(1), one Li(4), one Fe(2), and one Si(2) atom to form a mixture of corner and edge-sharing OLi2FeSi trigonal pyramids. In the seventh O site, O(7) is bonded to one Li(1), one Li(2), one Fe(1), and one Si(2) atom to form a mixture of distorted corner and edge-sharing OLi2FeSi tetrahedra. In the eighth O site, O(8) is bonded to one Li(3), one Li(4), one Fe(1), and one Si(2) atom to form corner-sharing OLi2FeSi tetrahedra. is represented by the CIF card [CIF]
data_Li2FeSiO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.806
_cell_length_b   5.405
_cell_length_c   6.289
_cell_angle_alpha   88.776
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   367.270
_cell_formula_units_Z   4
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  0.666  0.916  0.734  1.0
  Li  Li1  1  0.166  0.084  0.266  1.0
  Li  Li2  1  0.663  0.047  0.242  1.0
  Li  Li3  1  0.835  0.431  0.237  1.0
  Li  Li4  1  0.334  0.576  0.233  1.0
  Li  Li5  1  0.834  0.424  0.767  1.0
  Li  Li6  1  0.335  0.569  0.763  1.0
  Li  Li7  1  0.163  0.953  0.758  1.0
  Fe  Fe8  1  0.419  0.083  0.998  1.0
  Fe  Fe9  1  0.919  0.917  0.002  1.0
  Fe  Fe10  1  0.582  0.427  0.508  1.0
  Fe  Fe11  1  0.082  0.573  0.492  1.0
  Si  Si12  1  0.917  0.070  0.500  1.0
  Si  Si13  1  0.417  0.930  0.500  1.0
  Si  Si14  1  0.584  0.570  0.007  1.0
  Si  Si15  1  0.084  0.430  0.993  1.0
  O  O16  1  0.340  0.996  0.718  1.0
  O  O17  1  0.839  0.998  0.718  1.0
  O  O18  1  0.058  0.951  0.495  1.0
  O  O19  1  0.558  0.049  0.505  1.0
  O  O20  1  0.424  0.623  0.499  1.0
  O  O21  1  0.924  0.377  0.501  1.0
  O  O22  1  0.339  0.002  0.282  1.0
  O  O23  1  0.840  0.004  0.282  1.0
  O  O24  1  0.658  0.442  0.211  1.0
  O  O25  1  0.161  0.483  0.215  1.0
  O  O26  1  0.579  0.877  0.018  1.0
  O  O27  1  0.940  0.537  0.002  1.0
  O  O28  1  0.440  0.463  0.998  1.0
  O  O29  1  0.079  0.123  0.982  1.0
  O  O30  1  0.661  0.517  0.785  1.0
  O  O31  1  0.158  0.558  0.789  1.0
[/CIF]
.