The material described by W4Fe2S2O9 crystallizes in the triclinic P-1 space group. There are four inequivalent W sites. In the first W site, W(1) is bonded in a distorted L-shaped geometry to one O(3) and one O(8) atom. In the second W site, W(2) is bonded in a distorted single-bond geometry to one O(4) atom. In the third W site, W(3) is bonded in a 4-coordinate geometry to one O(1), one O(2), one O(3), and one O(6) atom. In the fourth W site, W(4) is bonded in a 3-coordinate geometry to one Fe(1), one O(4), and one O(5) atom. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a distorted water-like geometry to one W(4), one O(1), and one O(7) atom. In the second Fe site, Fe(2) is bonded to one O(2), one O(5), one O(6), and two equivalent O(1) atoms to form distorted FeO5 trigonal bipyramids that share  a cornercorner with one S(1)O4 tetrahedra, corners with two equivalent S(2)O4 tetrahedra, and  an edgeedge with one Fe(2)O5 trigonal bipyramid. There are two inequivalent S sites. In the first S site, S(1) is bonded to one O(3), one O(6), one O(7), and one O(8) atom to form SO4 tetrahedra that share  a cornercorner with one Fe(2)O5 trigonal bipyramid. In the second S site, S(2) is bonded to one O(2), one O(4), one O(5), and one O(9) atom to form SO4 tetrahedra that share corners with two equivalent Fe(2)O5 trigonal bipyramids. There are nine inequivalent O sites. In the first O site, O(9) is bonded in a single-bond geometry to one S(2) atom. In the second O site, O(1) is bonded to one W(3), one Fe(1), and two equivalent Fe(2) atoms to form edge-sharing OFe3W tetrahedra. In the third O site, O(2) is bonded in a 2-coordinate geometry to one W(3), one Fe(2), and one S(2) atom. In the fourth O site, O(3) is bonded in a 3-coordinate geometry to one W(1), one W(3), and one S(1) atom. In the fifth O site, O(4) is bonded in a distorted T-shaped geometry to one W(2), one W(4), and one S(2) atom. In the sixth O site, O(5) is bonded in a 3-coordinate geometry to one W(4), one Fe(2), and one S(2) atom. In the seventh O site, O(6) is bonded in a distorted trigonal non-coplanar geometry to one W(3), one Fe(2), and one S(1) atom. In the eighth O site, O(7) is bonded in a distorted bent 120 degrees geometry to one Fe(1) and one S(1) atom. In the ninth O site, O(8) is bonded in a 2-coordinate geometry to one W(1) and one S(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Fe2W4S2O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.528
_cell_length_b   6.456
_cell_length_c   10.803
_cell_angle_alpha   82.758
_cell_angle_beta   106.101
_cell_angle_gamma   87.050
_symmetry_Int_Tables_number   1
_cell_volume   564.610
_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
  Fe  Fe0  1  0.298  0.137  0.236  1.0
  Fe  Fe1  1  0.702  0.863  0.764  1.0
  Fe  Fe2  1  0.661  0.094  0.464  1.0
  Fe  Fe3  1  0.339  0.906  0.536  1.0
  W  W4  1  0.284  0.826  0.045  1.0
  W  W5  1  0.716  0.174  0.955  1.0
  W  W6  1  0.082  0.285  0.983  1.0
  W  W7  1  0.918  0.715  0.017  1.0
  W  W8  1  0.441  0.366  0.603  1.0
  W  W9  1  0.559  0.634  0.397  1.0
  W  W10  1  0.169  0.518  0.307  1.0
  W  W11  1  0.831  0.482  0.693  1.0
  S  S12  1  0.600  0.413  0.178  1.0
  S  S13  1  0.400  0.587  0.822  1.0
  S  S14  1  0.043  0.117  0.669  1.0
  S  S15  1  0.957  0.883  0.331  1.0
  O  O16  1  0.562  0.060  0.615  1.0
  O  O17  1  0.438  0.940  0.385  1.0
  O  O18  1  0.192  0.106  0.623  1.0
  O  O19  1  0.808  0.894  0.377  1.0
  O  O20  1  0.536  0.642  0.158  1.0
  O  O21  1  0.464  0.358  0.842  1.0
  O  O22  1  0.928  0.734  0.227  1.0
  O  O23  1  0.072  0.266  0.773  1.0
  O  O24  1  0.102  0.763  0.436  1.0
  O  O25  1  0.898  0.237  0.564  1.0
  O  O26  1  0.678  0.364  0.326  1.0
  O  O27  1  0.322  0.636  0.674  1.0
  O  O28  1  0.471  0.274  0.137  1.0
  O  O29  1  0.529  0.726  0.863  1.0
  O  O30  1  0.726  0.389  0.110  1.0
  O  O31  1  0.274  0.611  0.890  1.0
  O  O32  1  0.000  0.086  0.283  1.0
  O  O33  1  1.000  0.914  0.717  1.0
[/CIF]
.
The material described by W4Fe2S2O9 crystallizes in the triclinic P-1 space group. There are four inequivalent W sites. In the first W site, W(1) is bonded in a distorted L-shaped geometry to one O(3) and one O(8) atom. In the second W site, W(2) is bonded in a distorted single-bond geometry to one O(4) atom. In the third W site, W(3) is bonded in a 4-coordinate geometry to one O(1), one O(2), one O(3), and one O(6) atom. In the fourth W site, W(4) is bonded in a 3-coordinate geometry to one Fe(1), one O(4), and one O(5) atom. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a distorted water-like geometry to one W(4), one O(1), and one O(7) atom. In the second Fe site, Fe(2) is bonded to one O(2), one O(5), one O(6), and two equivalent O(1) atoms to form distorted FeO5 trigonal bipyramids that share  a cornercorner with one S(1)O4 tetrahedra, corners with two equivalent S(2)O4 tetrahedra, and  an edgeedge with one Fe(2)O5 trigonal bipyramid. There are two inequivalent S sites. In the first S site, S(1) is bonded to one O(3), one O(6), one O(7), and one O(8) atom to form SO4 tetrahedra that share  a cornercorner with one Fe(2)O5 trigonal bipyramid. In the second S site, S(2) is bonded to one O(2), one O(4), one O(5), and one O(9) atom to form SO4 tetrahedra that share corners with two equivalent Fe(2)O5 trigonal bipyramids. There are nine inequivalent O sites. In the first O site, O(9) is bonded in a single-bond geometry to one S(2) atom. In the second O site, O(1) is bonded to one W(3), one Fe(1), and two equivalent Fe(2) atoms to form edge-sharing OFe3W tetrahedra. In the third O site, O(2) is bonded in a 2-coordinate geometry to one W(3), one Fe(2), and one S(2) atom. In the fourth O site, O(3) is bonded in a 3-coordinate geometry to one W(1), one W(3), and one S(1) atom. In the fifth O site, O(4) is bonded in a distorted T-shaped geometry to one W(2), one W(4), and one S(2) atom. In the sixth O site, O(5) is bonded in a 3-coordinate geometry to one W(4), one Fe(2), and one S(2) atom. In the seventh O site, O(6) is bonded in a distorted trigonal non-coplanar geometry to one W(3), one Fe(2), and one S(1) atom. In the eighth O site, O(7) is bonded in a distorted bent 120 degrees geometry to one Fe(1) and one S(1) atom. In the ninth O site, O(8) is bonded in a 2-coordinate geometry to one W(1) and one S(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Fe2W4S2O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.528
_cell_length_b   6.456
_cell_length_c   10.803
_cell_angle_alpha   82.758
_cell_angle_beta   106.101
_cell_angle_gamma   87.050
_symmetry_Int_Tables_number   1
_cell_volume   564.610
_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
  Fe  Fe0  1  0.298  0.137  0.236  1.0
  Fe  Fe1  1  0.702  0.863  0.764  1.0
  Fe  Fe2  1  0.661  0.094  0.464  1.0
  Fe  Fe3  1  0.339  0.906  0.536  1.0
  W  W4  1  0.284  0.826  0.045  1.0
  W  W5  1  0.716  0.174  0.955  1.0
  W  W6  1  0.082  0.285  0.983  1.0
  W  W7  1  0.918  0.715  0.017  1.0
  W  W8  1  0.441  0.366  0.603  1.0
  W  W9  1  0.559  0.634  0.397  1.0
  W  W10  1  0.169  0.518  0.307  1.0
  W  W11  1  0.831  0.482  0.693  1.0
  S  S12  1  0.600  0.413  0.178  1.0
  S  S13  1  0.400  0.587  0.822  1.0
  S  S14  1  0.043  0.117  0.669  1.0
  S  S15  1  0.957  0.883  0.331  1.0
  O  O16  1  0.562  0.060  0.615  1.0
  O  O17  1  0.438  0.940  0.385  1.0
  O  O18  1  0.192  0.106  0.623  1.0
  O  O19  1  0.808  0.894  0.377  1.0
  O  O20  1  0.536  0.642  0.158  1.0
  O  O21  1  0.464  0.358  0.842  1.0
  O  O22  1  0.928  0.734  0.227  1.0
  O  O23  1  0.072  0.266  0.773  1.0
  O  O24  1  0.102  0.763  0.436  1.0
  O  O25  1  0.898  0.237  0.564  1.0
  O  O26  1  0.678  0.364  0.326  1.0
  O  O27  1  0.322  0.636  0.674  1.0
  O  O28  1  0.471  0.274  0.137  1.0
  O  O29  1  0.529  0.726  0.863  1.0
  O  O30  1  0.726  0.389  0.110  1.0
  O  O31  1  0.274  0.611  0.890  1.0
  O  O32  1  0.000  0.086  0.283  1.0
  O  O33  1  1.000  0.914  0.717  1.0
[/CIF]
.