The compound described by Li2FeS2 crystallizes in the monoclinic P2_1/c space group. There are four inequivalent Li sites. In the first Li site, Li(1) is bonded to one S(1), one S(2), and two equivalent S(4) atoms to form distorted LiS4 tetrahedra that share corners with two equivalent Li(1)S4 tetrahedra, corners with two equivalent Fe(2)S4 tetrahedra, corners with three equivalent Fe(1)S4 tetrahedra, and  an edgeedge with one Fe(2)S4 tetrahedra. In the second Li site, Li(2) is bonded in a distorted trigonal planar geometry to one S(1), one S(2), and one S(4) atom. In the third Li site, Li(3) is bonded in a 4-coordinate geometry to one S(1), one S(2), one S(3), and one S(4) atom. In the fourth Li site, Li(4) is bonded in a 4-coordinate geometry to one S(1), one S(3), and two equivalent S(2) atoms. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one S(2), one S(4), and two equivalent S(3) atoms to form distorted FeS4 tetrahedra that share  a cornercorner with one Fe(2)S4 tetrahedra, corners with three equivalent Li(1)S4 tetrahedra,  an edgeedge with one Fe(1)S4 tetrahedra, and  an edgeedge with one Fe(2)S4 tetrahedra. In the second Fe site, Fe(2) is bonded to one S(3), one S(4), and two equivalent S(1) atoms to form distorted FeS4 tetrahedra that share  a cornercorner with one Fe(1)S4 tetrahedra, corners with two equivalent Li(1)S4 tetrahedra,  an edgeedge with one Li(1)S4 tetrahedra,  an edgeedge with one Fe(1)S4 tetrahedra, and  an edgeedge with one Fe(2)S4 tetrahedra. There are four inequivalent S sites. In the first S site, S(1) is bonded in a 6-coordinate geometry to one Li(1), one Li(2), one Li(3), one Li(4), and two equivalent Fe(2) atoms. In the second S site, S(2) is bonded to one Li(1), one Li(2), one Li(3), two equivalent Li(4), and one Fe(1) atom to form SLi5Fe octahedra that share corners with two equivalent S(2)Li5Fe octahedra, corners with three equivalent S(4)Li4Fe2 octahedra, and  an edgeedge with one S(4)Li4Fe2 octahedra. The corner-sharing octahedral tilt angles range from 42-62°. In the third S site, S(3) is bonded in a 5-coordinate geometry to one Li(3), one Li(4), one Fe(2), and two equivalent Fe(1) atoms. In the fourth S site, S(4) is bonded to one Li(2), one Li(3), two equivalent Li(1), one Fe(1), and one Fe(2) atom to form distorted SLi4Fe2 octahedra that share corners with two equivalent S(4)Li4Fe2 octahedra, corners with three equivalent S(2)Li5Fe octahedra, and  an edgeedge with one S(2)Li5Fe octahedra. The corner-sharing octahedral tilt angles range from 44-65°. is represented by the CIF card [CIF]
data_Li2FeS2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.136
_cell_length_b   8.869
_cell_length_c   15.661
_cell_angle_alpha   58.273
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   724.870
_cell_formula_units_Z   8
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  0.983  0.648  0.753  1.0
  Li  Li1  1  0.442  0.616  0.838  1.0
  Li  Li2  1  0.876  0.854  0.452  1.0
  Li  Li3  1  0.969  0.081  0.188  1.0
  Li  Li4  1  0.469  0.919  0.312  1.0
  Li  Li5  1  0.376  0.146  0.048  1.0
  Li  Li6  1  0.942  0.384  0.662  1.0
  Li  Li7  1  0.483  0.352  0.747  1.0
  Li  Li8  1  0.517  0.648  0.253  1.0
  Li  Li9  1  0.058  0.616  0.338  1.0
  Li  Li10  1  0.624  0.854  0.952  1.0
  Li  Li11  1  0.531  0.081  0.688  1.0
  Li  Li12  1  0.031  0.919  0.812  1.0
  Li  Li13  1  0.124  0.146  0.548  1.0
  Li  Li14  1  0.558  0.384  0.162  1.0
  Li  Li15  1  0.017  0.352  0.247  1.0
  Fe  Fe16  1  0.491  0.872  0.590  1.0
  Fe  Fe17  1  0.985  0.372  0.975  1.0
  Fe  Fe18  1  0.485  0.628  0.525  1.0
  Fe  Fe19  1  0.991  0.128  0.910  1.0
  Fe  Fe20  1  0.009  0.872  0.090  1.0
  Fe  Fe21  1  0.515  0.372  0.475  1.0
  Fe  Fe22  1  0.015  0.628  0.025  1.0
  Fe  Fe23  1  0.509  0.128  0.410  1.0
  S  S24  1  0.205  0.359  0.100  1.0
  S  S25  1  0.740  0.127  0.296  1.0
  S  S26  1  0.270  0.882  0.460  1.0
  S  S27  1  0.717  0.627  0.644  1.0
  S  S28  1  0.217  0.373  0.856  1.0
  S  S29  1  0.770  0.118  0.040  1.0
  S  S30  1  0.295  0.359  0.600  1.0
  S  S31  1  0.240  0.873  0.204  1.0
  S  S32  1  0.760  0.127  0.796  1.0
  S  S33  1  0.705  0.641  0.400  1.0
  S  S34  1  0.230  0.882  0.960  1.0
  S  S35  1  0.783  0.627  0.144  1.0
  S  S36  1  0.283  0.373  0.356  1.0
  S  S37  1  0.730  0.118  0.540  1.0
  S  S38  1  0.260  0.873  0.704  1.0
  S  S39  1  0.795  0.641  0.900  1.0
[/CIF]
.
The compound described by Li2FeS2 crystallizes in the monoclinic P2_1/c space group. There are four inequivalent Li sites. In the first Li site, Li(1) is bonded to one S(1), one S(2), and two equivalent S(4) atoms to form distorted LiS4 tetrahedra that share corners with two equivalent Li(1)S4 tetrahedra, corners with two equivalent Fe(2)S4 tetrahedra, corners with three equivalent Fe(1)S4 tetrahedra, and  an edgeedge with one Fe(2)S4 tetrahedra. In the second Li site, Li(2) is bonded in a distorted trigonal planar geometry to one S(1), one S(2), and one S(4) atom. In the third Li site, Li(3) is bonded in a 4-coordinate geometry to one S(1), one S(2), one S(3), and one S(4) atom. In the fourth Li site, Li(4) is bonded in a 4-coordinate geometry to one S(1), one S(3), and two equivalent S(2) atoms. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one S(2), one S(4), and two equivalent S(3) atoms to form distorted FeS4 tetrahedra that share  a cornercorner with one Fe(2)S4 tetrahedra, corners with three equivalent Li(1)S4 tetrahedra,  an edgeedge with one Fe(1)S4 tetrahedra, and  an edgeedge with one Fe(2)S4 tetrahedra. In the second Fe site, Fe(2) is bonded to one S(3), one S(4), and two equivalent S(1) atoms to form distorted FeS4 tetrahedra that share  a cornercorner with one Fe(1)S4 tetrahedra, corners with two equivalent Li(1)S4 tetrahedra,  an edgeedge with one Li(1)S4 tetrahedra,  an edgeedge with one Fe(1)S4 tetrahedra, and  an edgeedge with one Fe(2)S4 tetrahedra. There are four inequivalent S sites. In the first S site, S(1) is bonded in a 6-coordinate geometry to one Li(1), one Li(2), one Li(3), one Li(4), and two equivalent Fe(2) atoms. In the second S site, S(2) is bonded to one Li(1), one Li(2), one Li(3), two equivalent Li(4), and one Fe(1) atom to form SLi5Fe octahedra that share corners with two equivalent S(2)Li5Fe octahedra, corners with three equivalent S(4)Li4Fe2 octahedra, and  an edgeedge with one S(4)Li4Fe2 octahedra. The corner-sharing octahedral tilt angles range from 42-62°. In the third S site, S(3) is bonded in a 5-coordinate geometry to one Li(3), one Li(4), one Fe(2), and two equivalent Fe(1) atoms. In the fourth S site, S(4) is bonded to one Li(2), one Li(3), two equivalent Li(1), one Fe(1), and one Fe(2) atom to form distorted SLi4Fe2 octahedra that share corners with two equivalent S(4)Li4Fe2 octahedra, corners with three equivalent S(2)Li5Fe octahedra, and  an edgeedge with one S(2)Li5Fe octahedra. The corner-sharing octahedral tilt angles range from 44-65°. is represented by the CIF card [CIF]
data_Li2FeS2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.136
_cell_length_b   8.869
_cell_length_c   15.661
_cell_angle_alpha   58.273
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   724.870
_cell_formula_units_Z   8
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  0.983  0.648  0.753  1.0
  Li  Li1  1  0.442  0.616  0.838  1.0
  Li  Li2  1  0.876  0.854  0.452  1.0
  Li  Li3  1  0.969  0.081  0.188  1.0
  Li  Li4  1  0.469  0.919  0.312  1.0
  Li  Li5  1  0.376  0.146  0.048  1.0
  Li  Li6  1  0.942  0.384  0.662  1.0
  Li  Li7  1  0.483  0.352  0.747  1.0
  Li  Li8  1  0.517  0.648  0.253  1.0
  Li  Li9  1  0.058  0.616  0.338  1.0
  Li  Li10  1  0.624  0.854  0.952  1.0
  Li  Li11  1  0.531  0.081  0.688  1.0
  Li  Li12  1  0.031  0.919  0.812  1.0
  Li  Li13  1  0.124  0.146  0.548  1.0
  Li  Li14  1  0.558  0.384  0.162  1.0
  Li  Li15  1  0.017  0.352  0.247  1.0
  Fe  Fe16  1  0.491  0.872  0.590  1.0
  Fe  Fe17  1  0.985  0.372  0.975  1.0
  Fe  Fe18  1  0.485  0.628  0.525  1.0
  Fe  Fe19  1  0.991  0.128  0.910  1.0
  Fe  Fe20  1  0.009  0.872  0.090  1.0
  Fe  Fe21  1  0.515  0.372  0.475  1.0
  Fe  Fe22  1  0.015  0.628  0.025  1.0
  Fe  Fe23  1  0.509  0.128  0.410  1.0
  S  S24  1  0.205  0.359  0.100  1.0
  S  S25  1  0.740  0.127  0.296  1.0
  S  S26  1  0.270  0.882  0.460  1.0
  S  S27  1  0.717  0.627  0.644  1.0
  S  S28  1  0.217  0.373  0.856  1.0
  S  S29  1  0.770  0.118  0.040  1.0
  S  S30  1  0.295  0.359  0.600  1.0
  S  S31  1  0.240  0.873  0.204  1.0
  S  S32  1  0.760  0.127  0.796  1.0
  S  S33  1  0.705  0.641  0.400  1.0
  S  S34  1  0.230  0.882  0.960  1.0
  S  S35  1  0.783  0.627  0.144  1.0
  S  S36  1  0.283  0.373  0.356  1.0
  S  S37  1  0.730  0.118  0.540  1.0
  S  S38  1  0.260  0.873  0.704  1.0
  S  S39  1  0.795  0.641  0.900  1.0
[/CIF]
.