The material structure described by RbCr3O8 crystallizes in the monoclinic C2/m space group. Rb(1) is bonded in a distorted q6 geometry to four equivalent O(3) and six equivalent O(2) atoms. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to two equivalent O(1) and four equivalent O(3) atoms to form corner-sharing CrO6 octahedra. In the second Cr site, Cr(2) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form corner-sharing CrO4 tetrahedra. The corner-sharing octahedral tilt angles range from 31-43°. There are three 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 distorted single-bond geometry to three equivalent Rb(1) and one Cr(2) atom. In the third O site, O(3) is bonded in a 2-coordinate geometry to one Rb(1), one Cr(1), and one Cr(2) atom. is represented by the CIF file [CIF]
data_RbCr3O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.090
_cell_length_b   5.090
_cell_length_c   7.986
_cell_angle_alpha   85.187
_cell_angle_beta   85.187
_cell_angle_gamma   64.694
_symmetry_Int_Tables_number   1
_cell_volume   186.101
_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
  Cr  Cr0  1  0.000  0.000  0.500  1.0
  Cr  Cr1  1  0.375  0.375  0.304  1.0
  Cr  Cr2  1  0.625  0.625  0.696  1.0
  O  O3  1  0.776  0.776  0.553  1.0
  O  O4  1  0.224  0.224  0.447  1.0
  O  O5  1  0.322  0.322  0.116  1.0
  O  O6  1  0.678  0.678  0.884  1.0
  O  O7  1  0.734  0.231  0.327  1.0
  O  O8  1  0.769  0.266  0.673  1.0
  O  O9  1  0.266  0.769  0.673  1.0
  O  O10  1  0.231  0.734  0.327  1.0
  Rb  Rb11  1  1.000  0.000  1.000  1.0
[/CIF]
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The material structure described by RbCr3O8 crystallizes in the monoclinic C2/m space group. Rb(1) is bonded in a distorted q6 geometry to four equivalent O(3) and six equivalent O(2) atoms. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to two equivalent O(1) and four equivalent O(3) atoms to form corner-sharing CrO6 octahedra. In the second Cr site, Cr(2) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form corner-sharing CrO4 tetrahedra. The corner-sharing octahedral tilt angles range from 31-43°. There are three 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 distorted single-bond geometry to three equivalent Rb(1) and one Cr(2) atom. In the third O site, O(3) is bonded in a 2-coordinate geometry to one Rb(1), one Cr(1), and one Cr(2) atom. is represented by the CIF file [CIF]
data_RbCr3O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.090
_cell_length_b   5.090
_cell_length_c   7.986
_cell_angle_alpha   85.187
_cell_angle_beta   85.187
_cell_angle_gamma   64.694
_symmetry_Int_Tables_number   1
_cell_volume   186.101
_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
  Cr  Cr0  1  0.000  0.000  0.500  1.0
  Cr  Cr1  1  0.375  0.375  0.304  1.0
  Cr  Cr2  1  0.625  0.625  0.696  1.0
  O  O3  1  0.776  0.776  0.553  1.0
  O  O4  1  0.224  0.224  0.447  1.0
  O  O5  1  0.322  0.322  0.116  1.0
  O  O6  1  0.678  0.678  0.884  1.0
  O  O7  1  0.734  0.231  0.327  1.0
  O  O8  1  0.769  0.266  0.673  1.0
  O  O9  1  0.266  0.769  0.673  1.0
  O  O10  1  0.231  0.734  0.327  1.0
  Rb  Rb11  1  1.000  0.000  1.000  1.0
[/CIF]
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