The compound described by Fe(SO4)2 crystallizes in the trigonal R3 space group. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to three equivalent O(2) and three equivalent O(6) atoms to form FeO6 octahedra that share corners with three equivalent S(1)O4 tetrahedra and corners with three equivalent S(2)O4 tetrahedra. In the second Fe site, Fe(2) is bonded to three equivalent O(7) and three equivalent O(8) atoms to form FeO6 octahedra that share corners with three equivalent S(1)O4 tetrahedra and corners with three equivalent S(2)O4 tetrahedra. In the third Fe site, Fe(3) is bonded to three equivalent O(3) and three equivalent O(5) atoms to form FeO6 octahedra that share corners with three equivalent S(1)O4 tetrahedra and corners with three equivalent S(2)O4 tetrahedra. There are two inequivalent S sites. In the first S site, S(1) is bonded to one O(2), one O(3), one O(4), and one O(8) atom to form SO4 tetrahedra that share  a cornercorner with one Fe(1)O6 octahedra,  a cornercorner with one Fe(2)O6 octahedra, and  a cornercorner with one Fe(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 25-41°. In the second S site, S(2) is bonded to one O(1), one O(5), one O(6), and one O(7) atom to form SO4 tetrahedra that share  a cornercorner with one Fe(1)O6 octahedra,  a cornercorner with one Fe(2)O6 octahedra, and  a cornercorner with one Fe(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 35-44°. There are eight inequivalent O sites. In the first O site, O(4) is bonded in a single-bond geometry to one S(1) atom. In the second O site, O(5) is bonded in a bent 150 degrees geometry to one Fe(3) and one S(2) atom. In the third O site, O(6) is bonded in a bent 150 degrees geometry to one Fe(1) and one S(2) atom. In the fourth O site, O(7) is bonded in a distorted bent 150 degrees geometry to one Fe(2) and one S(2) atom. In the fifth O site, O(8) is bonded in a bent 150 degrees geometry to one Fe(2) and one S(1) atom. In the sixth O site, O(1) is bonded in a single-bond geometry to one S(2) atom. In the seventh O site, O(2) is bonded in a bent 150 degrees geometry to one Fe(1) and one S(1) atom. In the eighth O site, O(3) is bonded in a bent 150 degrees geometry to one Fe(3) and one S(1) atom. is represented by the CIF card [CIF]
data_Fe(SO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.946
_cell_length_b   8.946
_cell_length_c   8.946
_cell_angle_alpha   55.713
_cell_angle_beta   55.713
_cell_angle_gamma   55.713
_symmetry_Int_Tables_number   1
_cell_volume   455.906
_cell_formula_units_Z   3
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  0.851  0.851  0.851  1.0
  Fe  Fe1  1  0.356  0.356  0.356  1.0
  Fe  Fe2  1  0.151  0.151  0.151  1.0
  S  S3  1  0.959  0.248  0.541  1.0
  S  S4  1  0.541  0.959  0.248  1.0
  S  S5  1  0.248  0.541  0.959  1.0
  S  S6  1  0.751  0.458  0.042  1.0
  S  S7  1  0.458  0.042  0.751  1.0
  S  S8  1  0.042  0.751  0.458  1.0
  O  O9  1  0.889  0.711  0.487  1.0
  O  O10  1  0.711  0.487  0.889  1.0
  O  O11  1  0.994  0.039  0.669  1.0
  O  O12  1  0.487  0.889  0.711  1.0
  O  O13  1  0.978  0.279  0.347  1.0
  O  O14  1  0.762  0.373  0.620  1.0
  O  O15  1  0.620  0.762  0.373  1.0
  O  O16  1  0.669  0.994  0.039  1.0
  O  O17  1  0.373  0.620  0.762  1.0
  O  O18  1  0.956  0.322  0.022  1.0
  O  O19  1  0.725  0.648  0.025  1.0
  O  O20  1  0.648  0.025  0.725  1.0
  O  O21  1  0.347  0.978  0.279  1.0
  O  O22  1  0.279  0.347  0.978  1.0
  O  O23  1  0.039  0.669  0.994  1.0
  O  O24  1  0.619  0.376  0.240  1.0
  O  O25  1  0.322  0.022  0.956  1.0
  O  O26  1  0.376  0.240  0.619  1.0
  O  O27  1  0.240  0.619  0.376  1.0
  O  O28  1  0.025  0.725  0.648  1.0
  O  O29  1  0.511  0.110  0.296  1.0
  O  O30  1  0.022  0.956  0.322  1.0
  O  O31  1  0.296  0.511  0.110  1.0
  O  O32  1  0.110  0.296  0.511  1.0
[/CIF]
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The compound described by Fe(SO4)2 crystallizes in the trigonal R3 space group. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to three equivalent O(2) and three equivalent O(6) atoms to form FeO6 octahedra that share corners with three equivalent S(1)O4 tetrahedra and corners with three equivalent S(2)O4 tetrahedra. In the second Fe site, Fe(2) is bonded to three equivalent O(7) and three equivalent O(8) atoms to form FeO6 octahedra that share corners with three equivalent S(1)O4 tetrahedra and corners with three equivalent S(2)O4 tetrahedra. In the third Fe site, Fe(3) is bonded to three equivalent O(3) and three equivalent O(5) atoms to form FeO6 octahedra that share corners with three equivalent S(1)O4 tetrahedra and corners with three equivalent S(2)O4 tetrahedra. There are two inequivalent S sites. In the first S site, S(1) is bonded to one O(2), one O(3), one O(4), and one O(8) atom to form SO4 tetrahedra that share  a cornercorner with one Fe(1)O6 octahedra,  a cornercorner with one Fe(2)O6 octahedra, and  a cornercorner with one Fe(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 25-41°. In the second S site, S(2) is bonded to one O(1), one O(5), one O(6), and one O(7) atom to form SO4 tetrahedra that share  a cornercorner with one Fe(1)O6 octahedra,  a cornercorner with one Fe(2)O6 octahedra, and  a cornercorner with one Fe(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 35-44°. There are eight inequivalent O sites. In the first O site, O(4) is bonded in a single-bond geometry to one S(1) atom. In the second O site, O(5) is bonded in a bent 150 degrees geometry to one Fe(3) and one S(2) atom. In the third O site, O(6) is bonded in a bent 150 degrees geometry to one Fe(1) and one S(2) atom. In the fourth O site, O(7) is bonded in a distorted bent 150 degrees geometry to one Fe(2) and one S(2) atom. In the fifth O site, O(8) is bonded in a bent 150 degrees geometry to one Fe(2) and one S(1) atom. In the sixth O site, O(1) is bonded in a single-bond geometry to one S(2) atom. In the seventh O site, O(2) is bonded in a bent 150 degrees geometry to one Fe(1) and one S(1) atom. In the eighth O site, O(3) is bonded in a bent 150 degrees geometry to one Fe(3) and one S(1) atom. is represented by the CIF card [CIF]
data_Fe(SO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.946
_cell_length_b   8.946
_cell_length_c   8.946
_cell_angle_alpha   55.713
_cell_angle_beta   55.713
_cell_angle_gamma   55.713
_symmetry_Int_Tables_number   1
_cell_volume   455.906
_cell_formula_units_Z   3
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  0.851  0.851  0.851  1.0
  Fe  Fe1  1  0.356  0.356  0.356  1.0
  Fe  Fe2  1  0.151  0.151  0.151  1.0
  S  S3  1  0.959  0.248  0.541  1.0
  S  S4  1  0.541  0.959  0.248  1.0
  S  S5  1  0.248  0.541  0.959  1.0
  S  S6  1  0.751  0.458  0.042  1.0
  S  S7  1  0.458  0.042  0.751  1.0
  S  S8  1  0.042  0.751  0.458  1.0
  O  O9  1  0.889  0.711  0.487  1.0
  O  O10  1  0.711  0.487  0.889  1.0
  O  O11  1  0.994  0.039  0.669  1.0
  O  O12  1  0.487  0.889  0.711  1.0
  O  O13  1  0.978  0.279  0.347  1.0
  O  O14  1  0.762  0.373  0.620  1.0
  O  O15  1  0.620  0.762  0.373  1.0
  O  O16  1  0.669  0.994  0.039  1.0
  O  O17  1  0.373  0.620  0.762  1.0
  O  O18  1  0.956  0.322  0.022  1.0
  O  O19  1  0.725  0.648  0.025  1.0
  O  O20  1  0.648  0.025  0.725  1.0
  O  O21  1  0.347  0.978  0.279  1.0
  O  O22  1  0.279  0.347  0.978  1.0
  O  O23  1  0.039  0.669  0.994  1.0
  O  O24  1  0.619  0.376  0.240  1.0
  O  O25  1  0.322  0.022  0.956  1.0
  O  O26  1  0.376  0.240  0.619  1.0
  O  O27  1  0.240  0.619  0.376  1.0
  O  O28  1  0.025  0.725  0.648  1.0
  O  O29  1  0.511  0.110  0.296  1.0
  O  O30  1  0.022  0.956  0.322  1.0
  O  O31  1  0.296  0.511  0.110  1.0
  O  O32  1  0.110  0.296  0.511  1.0
[/CIF]
.