The compound described by Li6FeS4 crystallizes in the tetragonal P4_2/nmc space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded to four equivalent S(1) atoms to form distorted LiS4 tetrahedra that share corners with two equivalent Fe(1)S4 tetrahedra, corners with four equivalent Li(2)S4 tetrahedra, corners with eight equivalent Li(1)S4 tetrahedra,  an edgeedge with one Fe(1)S4 tetrahedra, edges with two equivalent Li(1)S4 tetrahedra, and edges with two equivalent Li(2)S4 tetrahedra. In the second Li site, Li(2) is bonded to four equivalent S(1) atoms to form LiS4 tetrahedra that share corners with four equivalent Fe(1)S4 tetrahedra, corners with eight equivalent Li(1)S4 tetrahedra, edges with two equivalent Li(2)S4 tetrahedra, and edges with four equivalent Li(1)S4 tetrahedra. Fe(1) is bonded to four equivalent S(1) atoms to form FeS4 tetrahedra that share corners with eight equivalent Li(1)S4 tetrahedra, corners with eight equivalent Li(2)S4 tetrahedra, and edges with four equivalent Li(1)S4 tetrahedra. S(1) is bonded to two equivalent Li(2), four equivalent Li(1), and one Fe(1) atom to form a mixture of distorted corner and edge-sharing SLi6Fe pentagonal bipyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_Li6FeS4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.961
_cell_length_b   7.961
_cell_length_c   5.848
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   370.603
_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  0.273  0.273  0.500  1.0
  Li  Li1  1  0.727  0.273  0.500  1.0
  Li  Li2  1  0.000  0.500  0.460  1.0
  Li  Li3  1  0.000  0.500  0.960  1.0
  Li  Li4  1  0.273  0.727  0.500  1.0
  Li  Li5  1  0.727  0.727  0.500  1.0
  Li  Li6  1  0.773  0.773  0.000  1.0
  Li  Li7  1  0.227  0.773  0.000  1.0
  Li  Li8  1  0.500  0.000  0.040  1.0
  Li  Li9  1  0.500  0.000  0.540  1.0
  Li  Li10  1  0.773  0.227  0.000  1.0
  Li  Li11  1  0.227  0.227  0.000  1.0
  Fe  Fe12  1  0.500  0.500  0.000  1.0
  Fe  Fe13  1  0.000  0.000  0.500  1.0
  S  S14  1  0.000  0.254  0.716  1.0
  S  S15  1  0.754  0.500  0.216  1.0
  S  S16  1  0.246  0.500  0.216  1.0
  S  S17  1  0.000  0.746  0.716  1.0
  S  S18  1  0.500  0.754  0.784  1.0
  S  S19  1  0.746  0.000  0.284  1.0
  S  S20  1  0.254  0.000  0.284  1.0
  S  S21  1  0.500  0.246  0.784  1.0
[/CIF]
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The compound described by Li6FeS4 crystallizes in the tetragonal P4_2/nmc space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded to four equivalent S(1) atoms to form distorted LiS4 tetrahedra that share corners with two equivalent Fe(1)S4 tetrahedra, corners with four equivalent Li(2)S4 tetrahedra, corners with eight equivalent Li(1)S4 tetrahedra,  an edgeedge with one Fe(1)S4 tetrahedra, edges with two equivalent Li(1)S4 tetrahedra, and edges with two equivalent Li(2)S4 tetrahedra. In the second Li site, Li(2) is bonded to four equivalent S(1) atoms to form LiS4 tetrahedra that share corners with four equivalent Fe(1)S4 tetrahedra, corners with eight equivalent Li(1)S4 tetrahedra, edges with two equivalent Li(2)S4 tetrahedra, and edges with four equivalent Li(1)S4 tetrahedra. Fe(1) is bonded to four equivalent S(1) atoms to form FeS4 tetrahedra that share corners with eight equivalent Li(1)S4 tetrahedra, corners with eight equivalent Li(2)S4 tetrahedra, and edges with four equivalent Li(1)S4 tetrahedra. S(1) is bonded to two equivalent Li(2), four equivalent Li(1), and one Fe(1) atom to form a mixture of distorted corner and edge-sharing SLi6Fe pentagonal bipyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_Li6FeS4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.961
_cell_length_b   7.961
_cell_length_c   5.848
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   370.603
_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  0.273  0.273  0.500  1.0
  Li  Li1  1  0.727  0.273  0.500  1.0
  Li  Li2  1  0.000  0.500  0.460  1.0
  Li  Li3  1  0.000  0.500  0.960  1.0
  Li  Li4  1  0.273  0.727  0.500  1.0
  Li  Li5  1  0.727  0.727  0.500  1.0
  Li  Li6  1  0.773  0.773  0.000  1.0
  Li  Li7  1  0.227  0.773  0.000  1.0
  Li  Li8  1  0.500  0.000  0.040  1.0
  Li  Li9  1  0.500  0.000  0.540  1.0
  Li  Li10  1  0.773  0.227  0.000  1.0
  Li  Li11  1  0.227  0.227  0.000  1.0
  Fe  Fe12  1  0.500  0.500  0.000  1.0
  Fe  Fe13  1  0.000  0.000  0.500  1.0
  S  S14  1  0.000  0.254  0.716  1.0
  S  S15  1  0.754  0.500  0.216  1.0
  S  S16  1  0.246  0.500  0.216  1.0
  S  S17  1  0.000  0.746  0.716  1.0
  S  S18  1  0.500  0.754  0.784  1.0
  S  S19  1  0.746  0.000  0.284  1.0
  S  S20  1  0.254  0.000  0.284  1.0
  S  S21  1  0.500  0.246  0.784  1.0
[/CIF]
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