The structure described by CrO3 crystallizes in the monoclinic P2_1 space group. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom. In the second Cr site, Cr(2) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom. There are six inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one Cr(1) and one Cr(2) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Cr(1) and one Cr(2) atom. In the third O site, O(3) is bonded in a distorted bent 150 degrees geometry to one Cr(1) and one Cr(2) atom. In the fourth O site, O(4) is bonded in a distorted bent 150 degrees geometry to one Cr(1) and one Cr(2) atom. In the fifth O site, O(5) is bonded in a distorted bent 150 degrees geometry to one Cr(1) and one Cr(2) atom. In the sixth O site, O(6) is bonded in a distorted single-bond geometry to one Cr(1) and one Cr(2) atom. is represented by the CIF file [CIF]
data_CrO3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.259
_cell_length_b   5.001
_cell_length_c   7.129
_cell_angle_alpha   89.914
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   187.482
_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
  Cr  Cr0  1  0.052  0.756  0.780  1.0
  Cr  Cr1  1  0.547  0.228  0.720  1.0
  Cr  Cr2  1  0.552  0.244  0.220  1.0
  Cr  Cr3  1  0.047  0.772  0.280  1.0
  O  O4  1  0.503  0.344  0.002  1.0
  O  O5  1  0.964  0.836  0.499  1.0
  O  O6  1  0.003  0.656  0.998  1.0
  O  O7  1  0.464  0.164  0.501  1.0
  O  O8  1  0.279  0.554  0.298  1.0
  O  O9  1  0.185  0.046  0.207  1.0
  O  O10  1  0.779  0.446  0.702  1.0
  O  O11  1  0.685  0.954  0.793  1.0
  O  O12  1  0.285  0.562  0.705  1.0
  O  O13  1  0.183  0.050  0.803  1.0
  O  O14  1  0.683  0.950  0.197  1.0
  O  O15  1  0.785  0.438  0.295  1.0
[/CIF]
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The structure described by CrO3 crystallizes in the monoclinic P2_1 space group. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom. In the second Cr site, Cr(2) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom. There are six inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one Cr(1) and one Cr(2) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Cr(1) and one Cr(2) atom. In the third O site, O(3) is bonded in a distorted bent 150 degrees geometry to one Cr(1) and one Cr(2) atom. In the fourth O site, O(4) is bonded in a distorted bent 150 degrees geometry to one Cr(1) and one Cr(2) atom. In the fifth O site, O(5) is bonded in a distorted bent 150 degrees geometry to one Cr(1) and one Cr(2) atom. In the sixth O site, O(6) is bonded in a distorted single-bond geometry to one Cr(1) and one Cr(2) atom. is represented by the CIF file [CIF]
data_CrO3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.259
_cell_length_b   5.001
_cell_length_c   7.129
_cell_angle_alpha   89.914
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   187.482
_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
  Cr  Cr0  1  0.052  0.756  0.780  1.0
  Cr  Cr1  1  0.547  0.228  0.720  1.0
  Cr  Cr2  1  0.552  0.244  0.220  1.0
  Cr  Cr3  1  0.047  0.772  0.280  1.0
  O  O4  1  0.503  0.344  0.002  1.0
  O  O5  1  0.964  0.836  0.499  1.0
  O  O6  1  0.003  0.656  0.998  1.0
  O  O7  1  0.464  0.164  0.501  1.0
  O  O8  1  0.279  0.554  0.298  1.0
  O  O9  1  0.185  0.046  0.207  1.0
  O  O10  1  0.779  0.446  0.702  1.0
  O  O11  1  0.685  0.954  0.793  1.0
  O  O12  1  0.285  0.562  0.705  1.0
  O  O13  1  0.183  0.050  0.803  1.0
  O  O14  1  0.683  0.950  0.197  1.0
  O  O15  1  0.785  0.438  0.295  1.0
[/CIF]
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