The crystal structure described by CaSO4 is Zircon-like structured and crystallizes in the hexagonal P6_222 space group. Ca(1) is bonded to eight equivalent O(1) atoms to form distorted CaO8 hexagonal bipyramids that share corners with four equivalent S(1)O4 tetrahedra, edges with four equivalent Ca(1)O8 hexagonal bipyramids, and edges with two equivalent S(1)O4 tetrahedra. S(1) is bonded to four equivalent O(1) atoms to form SO4 tetrahedra that share corners with four equivalent Ca(1)O8 hexagonal bipyramids and edges with two equivalent Ca(1)O8 hexagonal bipyramids. O(1) is bonded in a 3-coordinate geometry to two equivalent Ca(1) and one S(1) atom. is represented by the CIF file [CIF]
data_CaSO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.974
_cell_length_b   6.974
_cell_length_c   6.275
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   264.330
_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
  Ca  Ca0  1  0.000  0.500  0.667  1.0
  Ca  Ca1  1  0.500  0.500  0.333  1.0
  Ca  Ca2  1  0.500  0.000  0.000  1.0
  S  S3  1  0.000  0.500  0.167  1.0
  S  S4  1  0.500  0.500  0.833  1.0
  S  S5  1  0.500  0.000  0.500  1.0
  O  O6  1  0.447  0.311  0.975  1.0
  O  O7  1  0.689  0.136  0.641  1.0
  O  O8  1  0.864  0.553  0.308  1.0
  O  O9  1  0.136  0.447  0.308  1.0
  O  O10  1  0.553  0.864  0.359  1.0
  O  O11  1  0.553  0.689  0.975  1.0
  O  O12  1  0.447  0.136  0.359  1.0
  O  O13  1  0.311  0.447  0.692  1.0
  O  O14  1  0.136  0.689  0.025  1.0
  O  O15  1  0.864  0.311  0.025  1.0
  O  O16  1  0.689  0.553  0.692  1.0
  O  O17  1  0.311  0.864  0.641  1.0
[/CIF]
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The crystal structure described by CaSO4 is Zircon-like structured and crystallizes in the hexagonal P6_222 space group. Ca(1) is bonded to eight equivalent O(1) atoms to form distorted CaO8 hexagonal bipyramids that share corners with four equivalent S(1)O4 tetrahedra, edges with four equivalent Ca(1)O8 hexagonal bipyramids, and edges with two equivalent S(1)O4 tetrahedra. S(1) is bonded to four equivalent O(1) atoms to form SO4 tetrahedra that share corners with four equivalent Ca(1)O8 hexagonal bipyramids and edges with two equivalent Ca(1)O8 hexagonal bipyramids. O(1) is bonded in a 3-coordinate geometry to two equivalent Ca(1) and one S(1) atom. is represented by the CIF file [CIF]
data_CaSO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.974
_cell_length_b   6.974
_cell_length_c   6.275
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   264.330
_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
  Ca  Ca0  1  0.000  0.500  0.667  1.0
  Ca  Ca1  1  0.500  0.500  0.333  1.0
  Ca  Ca2  1  0.500  0.000  0.000  1.0
  S  S3  1  0.000  0.500  0.167  1.0
  S  S4  1  0.500  0.500  0.833  1.0
  S  S5  1  0.500  0.000  0.500  1.0
  O  O6  1  0.447  0.311  0.975  1.0
  O  O7  1  0.689  0.136  0.641  1.0
  O  O8  1  0.864  0.553  0.308  1.0
  O  O9  1  0.136  0.447  0.308  1.0
  O  O10  1  0.553  0.864  0.359  1.0
  O  O11  1  0.553  0.689  0.975  1.0
  O  O12  1  0.447  0.136  0.359  1.0
  O  O13  1  0.311  0.447  0.692  1.0
  O  O14  1  0.136  0.689  0.025  1.0
  O  O15  1  0.864  0.311  0.025  1.0
  O  O16  1  0.689  0.553  0.692  1.0
  O  O17  1  0.311  0.864  0.641  1.0
[/CIF]
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