The structure described by Cr3MnO8 is Rutile-derived structured and crystallizes in the orthorhombic Cmc2_1 space group. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom to form CrO6 octahedra that share corners with two equivalent Mn(1)O6 octahedra,  an edgeedge with one Mn(1)O6 octahedra, edges with two equivalent Cr(1)O6 octahedra, and edges with two equivalent Cr(2)O6 octahedra. The corner-sharing octahedral tilt angles are 50°. In the second Cr site, Cr(2) is bonded to one O(3), one O(4), two equivalent O(1), and two equivalent O(5) atoms to form CrO6 octahedra that share corners with two equivalent Mn(1)O6 octahedra,  an edgeedge with one Mn(1)O6 octahedra, and edges with four equivalent Cr(1)O6 octahedra. The corner-sharing octahedral tilt angles are 52°. Mn(1) is bonded to one O(2), one O(6), two equivalent O(1), and two equivalent O(5) atoms to form MnO6 octahedra that share corners with two equivalent Cr(2)O6 octahedra, corners with four equivalent Cr(1)O6 octahedra,  an edgeedge with one Cr(2)O6 octahedra, and edges with two equivalent Cr(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 50-52°. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Cr(1), one Cr(2), and one Mn(1) atom. In the second O site, O(2) is bonded in a distorted trigonal non-coplanar geometry to two equivalent Cr(1) and one Mn(1) atom. In the third O site, O(3) is bonded in a distorted T-shaped geometry to one Cr(2) and two equivalent Cr(1) atoms. In the fourth O site, O(4) is bonded in a distorted trigonal non-coplanar geometry to one Cr(2) and two equivalent Cr(1) atoms. In the fifth O site, O(5) is bonded in a distorted trigonal non-coplanar geometry to one Cr(1), one Cr(2), and one Mn(1) atom. In the sixth O site, O(6) is bonded in a trigonal planar geometry to two equivalent Cr(1) and one Mn(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_MnCr3O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.837
_cell_length_b   5.889
_cell_length_c   8.885
_cell_angle_alpha   89.998
_cell_angle_beta   90.001
_cell_angle_gamma   120.297
_symmetry_Int_Tables_number   1
_cell_volume   263.737
_cell_formula_units_Z   2
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
  Mn  Mn0  1  0.326  0.663  0.483  1.0
  Mn  Mn1  1  0.674  0.337  0.983  1.0
  Cr  Cr2  1  0.163  0.832  0.202  1.0
  Cr  Cr3  1  0.163  0.331  0.202  1.0
  Cr  Cr4  1  0.657  0.828  0.219  1.0
  Cr  Cr5  1  0.343  0.171  0.719  1.0
  Cr  Cr6  1  0.837  0.669  0.702  1.0
  Cr  Cr7  1  0.837  0.168  0.702  1.0
  O  O8  1  0.161  0.823  0.605  1.0
  O  O9  1  0.050  0.525  0.337  1.0
  O  O10  1  0.345  0.673  0.098  1.0
  O  O11  1  0.990  0.995  0.311  1.0
  O  O12  1  0.010  0.005  0.811  1.0
  O  O13  1  0.161  0.338  0.605  1.0
  O  O14  1  0.472  0.950  0.343  1.0
  O  O15  1  0.472  0.522  0.343  1.0
  O  O16  1  0.346  0.173  0.110  1.0
  O  O17  1  0.654  0.827  0.610  1.0
  O  O18  1  0.528  0.478  0.843  1.0
  O  O19  1  0.528  0.050  0.843  1.0
  O  O20  1  0.655  0.327  0.598  1.0
  O  O21  1  0.839  0.662  0.105  1.0
  O  O22  1  0.950  0.475  0.837  1.0
  O  O23  1  0.839  0.177  0.105  1.0
[/CIF]
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The structure described by Cr3MnO8 is Rutile-derived structured and crystallizes in the orthorhombic Cmc2_1 space group. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom to form CrO6 octahedra that share corners with two equivalent Mn(1)O6 octahedra,  an edgeedge with one Mn(1)O6 octahedra, edges with two equivalent Cr(1)O6 octahedra, and edges with two equivalent Cr(2)O6 octahedra. The corner-sharing octahedral tilt angles are 50°. In the second Cr site, Cr(2) is bonded to one O(3), one O(4), two equivalent O(1), and two equivalent O(5) atoms to form CrO6 octahedra that share corners with two equivalent Mn(1)O6 octahedra,  an edgeedge with one Mn(1)O6 octahedra, and edges with four equivalent Cr(1)O6 octahedra. The corner-sharing octahedral tilt angles are 52°. Mn(1) is bonded to one O(2), one O(6), two equivalent O(1), and two equivalent O(5) atoms to form MnO6 octahedra that share corners with two equivalent Cr(2)O6 octahedra, corners with four equivalent Cr(1)O6 octahedra,  an edgeedge with one Cr(2)O6 octahedra, and edges with two equivalent Cr(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 50-52°. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Cr(1), one Cr(2), and one Mn(1) atom. In the second O site, O(2) is bonded in a distorted trigonal non-coplanar geometry to two equivalent Cr(1) and one Mn(1) atom. In the third O site, O(3) is bonded in a distorted T-shaped geometry to one Cr(2) and two equivalent Cr(1) atoms. In the fourth O site, O(4) is bonded in a distorted trigonal non-coplanar geometry to one Cr(2) and two equivalent Cr(1) atoms. In the fifth O site, O(5) is bonded in a distorted trigonal non-coplanar geometry to one Cr(1), one Cr(2), and one Mn(1) atom. In the sixth O site, O(6) is bonded in a trigonal planar geometry to two equivalent Cr(1) and one Mn(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_MnCr3O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.837
_cell_length_b   5.889
_cell_length_c   8.885
_cell_angle_alpha   89.998
_cell_angle_beta   90.001
_cell_angle_gamma   120.297
_symmetry_Int_Tables_number   1
_cell_volume   263.737
_cell_formula_units_Z   2
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
  Mn  Mn0  1  0.326  0.663  0.483  1.0
  Mn  Mn1  1  0.674  0.337  0.983  1.0
  Cr  Cr2  1  0.163  0.832  0.202  1.0
  Cr  Cr3  1  0.163  0.331  0.202  1.0
  Cr  Cr4  1  0.657  0.828  0.219  1.0
  Cr  Cr5  1  0.343  0.171  0.719  1.0
  Cr  Cr6  1  0.837  0.669  0.702  1.0
  Cr  Cr7  1  0.837  0.168  0.702  1.0
  O  O8  1  0.161  0.823  0.605  1.0
  O  O9  1  0.050  0.525  0.337  1.0
  O  O10  1  0.345  0.673  0.098  1.0
  O  O11  1  0.990  0.995  0.311  1.0
  O  O12  1  0.010  0.005  0.811  1.0
  O  O13  1  0.161  0.338  0.605  1.0
  O  O14  1  0.472  0.950  0.343  1.0
  O  O15  1  0.472  0.522  0.343  1.0
  O  O16  1  0.346  0.173  0.110  1.0
  O  O17  1  0.654  0.827  0.610  1.0
  O  O18  1  0.528  0.478  0.843  1.0
  O  O19  1  0.528  0.050  0.843  1.0
  O  O20  1  0.655  0.327  0.598  1.0
  O  O21  1  0.839  0.662  0.105  1.0
  O  O22  1  0.950  0.475  0.837  1.0
  O  O23  1  0.839  0.177  0.105  1.0
[/CIF]
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