The structure described by MgCrFe(BiO3)2 crystallizes in the triclinic P1 space group. Mg(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 MgO6 octahedra that share  a cornercorner with one Cr(1)O5 trigonal bipyramid, edges with three equivalent Bi(1)O6 octahedra, and edges with two equivalent Cr(1)O5 trigonal bipyramids. Cr(1) is bonded to one O(1), one O(2), one O(3), one O(5), and one O(6) atom to form distorted CrO5 trigonal bipyramids that share  a cornercorner with one Mg(1)O6 octahedra,  a cornercorner with one Bi(1)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, and edges with two equivalent Bi(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 79-82°. Fe(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. There are two inequivalent Bi sites. In the first Bi site, Bi(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 distorted BiO6 octahedra that share  a cornercorner with one Cr(1)O5 trigonal bipyramid, edges with three equivalent Mg(1)O6 octahedra, and edges with two equivalent Cr(1)O5 trigonal bipyramids. In the second Bi site, Bi(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 5-coordinate geometry to one Mg(1), one Cr(1), one Fe(1), one Bi(1), and one Bi(2) atom. In the second O site, O(2) is bonded in a 5-coordinate geometry to one Mg(1), one Cr(1), one Fe(1), one Bi(1), and one Bi(2) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Mg(1), one Cr(1), one Fe(1), one Bi(1), and one Bi(2) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Mg(1), one Fe(1), one Bi(1), and one Bi(2) atom. In the fifth O site, O(5) is bonded in a 5-coordinate geometry to one Mg(1), one Cr(1), one Fe(1), one Bi(1), and one Bi(2) atom. In the sixth O site, O(6) is bonded in a 5-coordinate geometry to one Mg(1), one Cr(1), one Fe(1), one Bi(1), and one Bi(2) atom. is represented by the CIF file [CIF]
data_MgCrFe(BiO3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.425
_cell_length_b   6.531
_cell_length_c   6.514
_cell_angle_alpha   52.039
_cell_angle_beta   51.563
_cell_angle_gamma   51.237
_symmetry_Int_Tables_number   1
_cell_volume   155.111
_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
  Mg  Mg0  1  0.866  0.870  0.882  1.0
  Cr  Cr1  1  0.236  0.226  0.238  1.0
  Fe  Fe2  1  0.686  0.697  0.708  1.0
  Bi  Bi3  1  0.520  0.517  0.524  1.0
  Bi  Bi4  1  0.030  0.051  0.072  1.0
  O  O5  1  0.301  0.669  0.914  1.0
  O  O6  1  0.906  0.276  0.636  1.0
  O  O7  1  0.881  0.465  0.110  1.0
  O  O8  1  0.001  0.818  0.517  1.0
  O  O9  1  0.619  0.908  0.309  1.0
  O  O10  1  0.447  0.067  0.916  1.0
[/CIF]
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The structure described by MgCrFe(BiO3)2 crystallizes in the triclinic P1 space group. Mg(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 MgO6 octahedra that share  a cornercorner with one Cr(1)O5 trigonal bipyramid, edges with three equivalent Bi(1)O6 octahedra, and edges with two equivalent Cr(1)O5 trigonal bipyramids. Cr(1) is bonded to one O(1), one O(2), one O(3), one O(5), and one O(6) atom to form distorted CrO5 trigonal bipyramids that share  a cornercorner with one Mg(1)O6 octahedra,  a cornercorner with one Bi(1)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, and edges with two equivalent Bi(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 79-82°. Fe(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. There are two inequivalent Bi sites. In the first Bi site, Bi(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 distorted BiO6 octahedra that share  a cornercorner with one Cr(1)O5 trigonal bipyramid, edges with three equivalent Mg(1)O6 octahedra, and edges with two equivalent Cr(1)O5 trigonal bipyramids. In the second Bi site, Bi(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 5-coordinate geometry to one Mg(1), one Cr(1), one Fe(1), one Bi(1), and one Bi(2) atom. In the second O site, O(2) is bonded in a 5-coordinate geometry to one Mg(1), one Cr(1), one Fe(1), one Bi(1), and one Bi(2) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Mg(1), one Cr(1), one Fe(1), one Bi(1), and one Bi(2) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Mg(1), one Fe(1), one Bi(1), and one Bi(2) atom. In the fifth O site, O(5) is bonded in a 5-coordinate geometry to one Mg(1), one Cr(1), one Fe(1), one Bi(1), and one Bi(2) atom. In the sixth O site, O(6) is bonded in a 5-coordinate geometry to one Mg(1), one Cr(1), one Fe(1), one Bi(1), and one Bi(2) atom. is represented by the CIF file [CIF]
data_MgCrFe(BiO3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.425
_cell_length_b   6.531
_cell_length_c   6.514
_cell_angle_alpha   52.039
_cell_angle_beta   51.563
_cell_angle_gamma   51.237
_symmetry_Int_Tables_number   1
_cell_volume   155.111
_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
  Mg  Mg0  1  0.866  0.870  0.882  1.0
  Cr  Cr1  1  0.236  0.226  0.238  1.0
  Fe  Fe2  1  0.686  0.697  0.708  1.0
  Bi  Bi3  1  0.520  0.517  0.524  1.0
  Bi  Bi4  1  0.030  0.051  0.072  1.0
  O  O5  1  0.301  0.669  0.914  1.0
  O  O6  1  0.906  0.276  0.636  1.0
  O  O7  1  0.881  0.465  0.110  1.0
  O  O8  1  0.001  0.818  0.517  1.0
  O  O9  1  0.619  0.908  0.309  1.0
  O  O10  1  0.447  0.067  0.916  1.0
[/CIF]
.