The crystal structure described by CaSeO3 crystallizes in the monoclinic P2_1/c space group. Ca(1) is bonded in a 7-coordinate geometry to two equivalent O(1), two equivalent O(3), and three equivalent O(2) atoms. Se(1) is bonded in a trigonal non-coplanar geometry to one O(1), one O(2), and one O(3) atom. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to two equivalent Ca(1) and one Se(1) atom. In the second O site, O(2) is bonded to three equivalent Ca(1) and one Se(1) atom to form a mixture of distorted edge and corner-sharing OCa3Se tetrahedra. In the third O site, O(3) is bonded in a distorted trigonal non-coplanar geometry to two equivalent Ca(1) and one Se(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_CaSeO3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.393
_cell_length_b   6.694
_cell_length_c   6.806
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   102.658
_symmetry_Int_Tables_number   1
_cell_volume   284.231
_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
  Ca  Ca0  1  0.725  0.876  0.872  1.0
  Ca  Ca1  1  0.225  0.376  0.628  1.0
  Ca  Ca2  1  0.775  0.624  0.372  1.0
  Ca  Ca3  1  0.275  0.124  0.128  1.0
  Se  Se4  1  0.741  0.096  0.337  1.0
  Se  Se5  1  0.241  0.596  0.163  1.0
  Se  Se6  1  0.759  0.404  0.837  1.0
  Se  Se7  1  0.259  0.904  0.663  1.0
  O  O8  1  0.914  0.312  0.417  1.0
  O  O9  1  0.586  0.188  0.917  1.0
  O  O10  1  0.605  0.520  0.686  1.0
  O  O11  1  0.414  0.812  0.083  1.0
  O  O12  1  0.783  0.571  0.028  1.0
  O  O13  1  0.086  0.688  0.583  1.0
  O  O14  1  0.217  0.429  0.972  1.0
  O  O15  1  0.105  0.020  0.814  1.0
  O  O16  1  0.283  0.071  0.472  1.0
  O  O17  1  0.395  0.480  0.314  1.0
  O  O18  1  0.895  0.980  0.186  1.0
  O  O19  1  0.717  0.929  0.528  1.0
[/CIF]
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The crystal structure described by CaSeO3 crystallizes in the monoclinic P2_1/c space group. Ca(1) is bonded in a 7-coordinate geometry to two equivalent O(1), two equivalent O(3), and three equivalent O(2) atoms. Se(1) is bonded in a trigonal non-coplanar geometry to one O(1), one O(2), and one O(3) atom. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to two equivalent Ca(1) and one Se(1) atom. In the second O site, O(2) is bonded to three equivalent Ca(1) and one Se(1) atom to form a mixture of distorted edge and corner-sharing OCa3Se tetrahedra. In the third O site, O(3) is bonded in a distorted trigonal non-coplanar geometry to two equivalent Ca(1) and one Se(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_CaSeO3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.393
_cell_length_b   6.694
_cell_length_c   6.806
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   102.658
_symmetry_Int_Tables_number   1
_cell_volume   284.231
_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
  Ca  Ca0  1  0.725  0.876  0.872  1.0
  Ca  Ca1  1  0.225  0.376  0.628  1.0
  Ca  Ca2  1  0.775  0.624  0.372  1.0
  Ca  Ca3  1  0.275  0.124  0.128  1.0
  Se  Se4  1  0.741  0.096  0.337  1.0
  Se  Se5  1  0.241  0.596  0.163  1.0
  Se  Se6  1  0.759  0.404  0.837  1.0
  Se  Se7  1  0.259  0.904  0.663  1.0
  O  O8  1  0.914  0.312  0.417  1.0
  O  O9  1  0.586  0.188  0.917  1.0
  O  O10  1  0.605  0.520  0.686  1.0
  O  O11  1  0.414  0.812  0.083  1.0
  O  O12  1  0.783  0.571  0.028  1.0
  O  O13  1  0.086  0.688  0.583  1.0
  O  O14  1  0.217  0.429  0.972  1.0
  O  O15  1  0.105  0.020  0.814  1.0
  O  O16  1  0.283  0.071  0.472  1.0
  O  O17  1  0.395  0.480  0.314  1.0
  O  O18  1  0.895  0.980  0.186  1.0
  O  O19  1  0.717  0.929  0.528  1.0
[/CIF]
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