The compound described by YCr3O9 crystallizes in the tetragonal P4/mmm space group. Y(1) is bonded to four equivalent O(1) and eight equivalent O(3) atoms to form a mixture of face and corner-sharing YO12 cuboctahedra. 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), and four equivalent O(3) atoms. In the second Cr site, Cr(2) is bonded to two equivalent O(2) and four equivalent O(4) atoms to form corner-sharing CrO6 octahedra. The corner-sharing octahedra are not tilted. There are four inequivalent O sites. In the first O site, O(1) is bonded to four equivalent Y(1) and two equivalent Cr(1) atoms to form a mixture of corner and edge-sharing OY4Cr2 octahedra. The corner-sharing octahedra are not tilted. In the second O site, O(2) is bonded in a linear 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 two equivalent Y(1) and two equivalent Cr(1) atoms. In the fourth O site, O(4) is bonded in a linear geometry to two equivalent Cr(2) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_YCr3O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.685
_cell_length_b   3.685
_cell_length_c   11.521
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   156.469
_cell_formula_units_Z   1
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
  Y  Y0  1  0.000  0.000  0.000  1.0
  Cr  Cr1  1  0.500  0.500  0.184  1.0
  Cr  Cr2  1  0.500  0.500  0.500  1.0
  Cr  Cr3  1  0.500  0.500  0.816  1.0
  O  O4  1  0.500  0.500  0.000  1.0
  O  O5  1  0.500  0.500  0.328  1.0
  O  O6  1  0.500  0.500  0.672  1.0
  O  O7  1  0.500  0.000  0.147  1.0
  O  O8  1  0.500  0.000  0.500  1.0
  O  O9  1  0.500  0.000  0.853  1.0
  O  O10  1  0.000  0.500  0.147  1.0
  O  O11  1  0.000  0.500  0.500  1.0
  O  O12  1  0.000  0.500  0.853  1.0
[/CIF]
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The compound described by YCr3O9 crystallizes in the tetragonal P4/mmm space group. Y(1) is bonded to four equivalent O(1) and eight equivalent O(3) atoms to form a mixture of face and corner-sharing YO12 cuboctahedra. 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), and four equivalent O(3) atoms. In the second Cr site, Cr(2) is bonded to two equivalent O(2) and four equivalent O(4) atoms to form corner-sharing CrO6 octahedra. The corner-sharing octahedra are not tilted. There are four inequivalent O sites. In the first O site, O(1) is bonded to four equivalent Y(1) and two equivalent Cr(1) atoms to form a mixture of corner and edge-sharing OY4Cr2 octahedra. The corner-sharing octahedra are not tilted. In the second O site, O(2) is bonded in a linear 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 two equivalent Y(1) and two equivalent Cr(1) atoms. In the fourth O site, O(4) is bonded in a linear geometry to two equivalent Cr(2) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_YCr3O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.685
_cell_length_b   3.685
_cell_length_c   11.521
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   156.469
_cell_formula_units_Z   1
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
  Y  Y0  1  0.000  0.000  0.000  1.0
  Cr  Cr1  1  0.500  0.500  0.184  1.0
  Cr  Cr2  1  0.500  0.500  0.500  1.0
  Cr  Cr3  1  0.500  0.500  0.816  1.0
  O  O4  1  0.500  0.500  0.000  1.0
  O  O5  1  0.500  0.500  0.328  1.0
  O  O6  1  0.500  0.500  0.672  1.0
  O  O7  1  0.500  0.000  0.147  1.0
  O  O8  1  0.500  0.000  0.500  1.0
  O  O9  1  0.500  0.000  0.853  1.0
  O  O10  1  0.000  0.500  0.147  1.0
  O  O11  1  0.000  0.500  0.500  1.0
  O  O12  1  0.000  0.500  0.853  1.0
[/CIF]
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