The structure described by Fe2SiS4 is Spinel-like structured and crystallizes in the orthorhombic Pnma space group. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one S(1), one S(2), and four equivalent S(3) atoms to form FeS6 octahedra that share corners with four equivalent Fe(1)S6 octahedra, corners with four equivalent Fe(2)S6 octahedra, corners with four equivalent Si(1)S4 tetrahedra, edges with two equivalent Fe(2)S6 octahedra, and  an edgeedge with one Si(1)S4 tetrahedra. The corner-sharing octahedral tilt angles range from 47-53°. In the second Fe site, Fe(2) is bonded to two equivalent S(1), two equivalent S(2), and two equivalent S(3) atoms to form FeS6 octahedra that share corners with four equivalent Fe(1)S6 octahedra, corners with two equivalent Si(1)S4 tetrahedra, edges with two equivalent Fe(1)S6 octahedra, edges with two equivalent Fe(2)S6 octahedra, and edges with two equivalent Si(1)S4 tetrahedra. The corner-sharing octahedral tilt angles range from 49-53°. Si(1) is bonded to one S(1), one S(2), and two equivalent S(3) atoms to form SiS4 tetrahedra that share corners with two equivalent Fe(2)S6 octahedra, corners with four equivalent Fe(1)S6 octahedra,  an edgeedge with one Fe(1)S6 octahedra, and edges with two equivalent Fe(2)S6 octahedra. The corner-sharing octahedral tilt angles range from 58-61°. There are three inequivalent S sites. In the first S site, S(1) is bonded in a rectangular see-saw-like geometry to one Fe(1), two equivalent Fe(2), and one Si(1) atom. In the second S site, S(2) is bonded to one Fe(1), two equivalent Fe(2), and one Si(1) atom to form distorted corner-sharing SFe3Si trigonal pyramids. In the third S site, S(3) is bonded in a rectangular see-saw-like geometry to one Fe(2), two equivalent Fe(1), and one Si(1) atom. is represented by the CIF file [CIF]
data_Fe2SiS4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.808
_cell_length_b   7.027
_cell_length_c   12.167
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   496.558
_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
  Fe  Fe0  1  0.507  0.750  0.738  1.0
  Fe  Fe1  1  0.007  0.250  0.762  1.0
  Fe  Fe2  1  0.000  0.000  0.500  1.0
  Fe  Fe3  1  0.493  0.250  0.262  1.0
  Fe  Fe4  1  0.993  0.750  0.238  1.0
  Fe  Fe5  1  0.500  0.000  0.000  1.0
  Fe  Fe6  1  0.500  0.500  0.000  1.0
  Fe  Fe7  1  0.000  0.500  0.500  1.0
  Si  Si8  1  0.908  0.250  0.088  1.0
  Si  Si9  1  0.092  0.750  0.912  1.0
  Si  Si10  1  0.592  0.250  0.588  1.0
  Si  Si11  1  0.408  0.750  0.412  1.0
  S  S12  1  0.259  0.750  0.575  1.0
  S  S13  1  0.223  0.250  0.592  1.0
  S  S14  1  0.251  0.509  0.832  1.0
  S  S15  1  0.741  0.250  0.425  1.0
  S  S16  1  0.751  0.009  0.668  1.0
  S  S17  1  0.751  0.491  0.668  1.0
  S  S18  1  0.249  0.509  0.332  1.0
  S  S19  1  0.277  0.250  0.092  1.0
  S  S20  1  0.241  0.750  0.075  1.0
  S  S21  1  0.723  0.750  0.908  1.0
  S  S22  1  0.251  0.991  0.832  1.0
  S  S23  1  0.777  0.750  0.408  1.0
  S  S24  1  0.749  0.009  0.168  1.0
  S  S25  1  0.759  0.250  0.925  1.0
  S  S26  1  0.249  0.991  0.332  1.0
  S  S27  1  0.749  0.491  0.168  1.0
[/CIF]
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The structure described by Fe2SiS4 is Spinel-like structured and crystallizes in the orthorhombic Pnma space group. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one S(1), one S(2), and four equivalent S(3) atoms to form FeS6 octahedra that share corners with four equivalent Fe(1)S6 octahedra, corners with four equivalent Fe(2)S6 octahedra, corners with four equivalent Si(1)S4 tetrahedra, edges with two equivalent Fe(2)S6 octahedra, and  an edgeedge with one Si(1)S4 tetrahedra. The corner-sharing octahedral tilt angles range from 47-53°. In the second Fe site, Fe(2) is bonded to two equivalent S(1), two equivalent S(2), and two equivalent S(3) atoms to form FeS6 octahedra that share corners with four equivalent Fe(1)S6 octahedra, corners with two equivalent Si(1)S4 tetrahedra, edges with two equivalent Fe(1)S6 octahedra, edges with two equivalent Fe(2)S6 octahedra, and edges with two equivalent Si(1)S4 tetrahedra. The corner-sharing octahedral tilt angles range from 49-53°. Si(1) is bonded to one S(1), one S(2), and two equivalent S(3) atoms to form SiS4 tetrahedra that share corners with two equivalent Fe(2)S6 octahedra, corners with four equivalent Fe(1)S6 octahedra,  an edgeedge with one Fe(1)S6 octahedra, and edges with two equivalent Fe(2)S6 octahedra. The corner-sharing octahedral tilt angles range from 58-61°. There are three inequivalent S sites. In the first S site, S(1) is bonded in a rectangular see-saw-like geometry to one Fe(1), two equivalent Fe(2), and one Si(1) atom. In the second S site, S(2) is bonded to one Fe(1), two equivalent Fe(2), and one Si(1) atom to form distorted corner-sharing SFe3Si trigonal pyramids. In the third S site, S(3) is bonded in a rectangular see-saw-like geometry to one Fe(2), two equivalent Fe(1), and one Si(1) atom. is represented by the CIF file [CIF]
data_Fe2SiS4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.808
_cell_length_b   7.027
_cell_length_c   12.167
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   496.558
_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
  Fe  Fe0  1  0.507  0.750  0.738  1.0
  Fe  Fe1  1  0.007  0.250  0.762  1.0
  Fe  Fe2  1  0.000  0.000  0.500  1.0
  Fe  Fe3  1  0.493  0.250  0.262  1.0
  Fe  Fe4  1  0.993  0.750  0.238  1.0
  Fe  Fe5  1  0.500  0.000  0.000  1.0
  Fe  Fe6  1  0.500  0.500  0.000  1.0
  Fe  Fe7  1  0.000  0.500  0.500  1.0
  Si  Si8  1  0.908  0.250  0.088  1.0
  Si  Si9  1  0.092  0.750  0.912  1.0
  Si  Si10  1  0.592  0.250  0.588  1.0
  Si  Si11  1  0.408  0.750  0.412  1.0
  S  S12  1  0.259  0.750  0.575  1.0
  S  S13  1  0.223  0.250  0.592  1.0
  S  S14  1  0.251  0.509  0.832  1.0
  S  S15  1  0.741  0.250  0.425  1.0
  S  S16  1  0.751  0.009  0.668  1.0
  S  S17  1  0.751  0.491  0.668  1.0
  S  S18  1  0.249  0.509  0.332  1.0
  S  S19  1  0.277  0.250  0.092  1.0
  S  S20  1  0.241  0.750  0.075  1.0
  S  S21  1  0.723  0.750  0.908  1.0
  S  S22  1  0.251  0.991  0.832  1.0
  S  S23  1  0.777  0.750  0.408  1.0
  S  S24  1  0.749  0.009  0.168  1.0
  S  S25  1  0.759  0.250  0.925  1.0
  S  S26  1  0.249  0.991  0.332  1.0
  S  S27  1  0.749  0.491  0.168  1.0
[/CIF]
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