The material described by BaCr4O7 crystallizes in the hexagonal P6_3mc space group. Ba(1) is bonded in a 9-coordinate geometry to three equivalent O(3) and six equivalent O(1) atoms. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form corner-sharing CrO4 tetrahedra. In the second Cr site, Cr(2) is bonded to one O(2) and three equivalent O(1) atoms to form corner-sharing CrO4 tetrahedra. There are three inequivalent O sites. In the first O site, O(1) is bonded in a bent 120 degrees geometry to two equivalent Ba(1), one Cr(1), and one Cr(2) atom. In the second O site, O(2) is bonded in a tetrahedral geometry to one Cr(2) and three equivalent Cr(1) atoms. In the third O site, O(3) is bonded in a distorted bent 120 degrees geometry to one Ba(1) and two equivalent Cr(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_BaCr4O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.690
_cell_length_b   6.690
_cell_length_c   10.551
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   408.939
_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
  Ba  Ba0  1  0.667  0.333  0.476  1.0
  Ba  Ba1  1  0.333  0.667  0.976  1.0
  Cr  Cr2  1  0.828  0.172  0.191  1.0
  Cr  Cr3  1  0.656  0.828  0.691  1.0
  Cr  Cr4  1  0.172  0.344  0.691  1.0
  Cr  Cr5  1  0.828  0.656  0.191  1.0
  Cr  Cr6  1  0.344  0.172  0.191  1.0
  Cr  Cr7  1  0.172  0.828  0.691  1.0
  Cr  Cr8  1  0.000  0.000  0.442  1.0
  Cr  Cr9  1  0.000  0.000  0.942  1.0
  O  O10  1  0.856  0.144  0.017  1.0
  O  O11  1  0.711  0.856  0.517  1.0
  O  O12  1  0.144  0.289  0.517  1.0
  O  O13  1  0.856  0.711  0.017  1.0
  O  O14  1  0.289  0.144  0.017  1.0
  O  O15  1  0.144  0.856  0.517  1.0
  O  O16  1  0.000  0.000  0.745  1.0
  O  O17  1  0.000  0.000  0.245  1.0
  O  O18  1  0.527  0.473  0.256  1.0
  O  O19  1  0.055  0.527  0.756  1.0
  O  O20  1  0.473  0.945  0.756  1.0
  O  O21  1  0.527  0.055  0.256  1.0
  O  O22  1  0.473  0.527  0.756  1.0
  O  O23  1  0.945  0.473  0.256  1.0
[/CIF]
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The material described by BaCr4O7 crystallizes in the hexagonal P6_3mc space group. Ba(1) is bonded in a 9-coordinate geometry to three equivalent O(3) and six equivalent O(1) atoms. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form corner-sharing CrO4 tetrahedra. In the second Cr site, Cr(2) is bonded to one O(2) and three equivalent O(1) atoms to form corner-sharing CrO4 tetrahedra. There are three inequivalent O sites. In the first O site, O(1) is bonded in a bent 120 degrees geometry to two equivalent Ba(1), one Cr(1), and one Cr(2) atom. In the second O site, O(2) is bonded in a tetrahedral geometry to one Cr(2) and three equivalent Cr(1) atoms. In the third O site, O(3) is bonded in a distorted bent 120 degrees geometry to one Ba(1) and two equivalent Cr(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_BaCr4O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.690
_cell_length_b   6.690
_cell_length_c   10.551
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   408.939
_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
  Ba  Ba0  1  0.667  0.333  0.476  1.0
  Ba  Ba1  1  0.333  0.667  0.976  1.0
  Cr  Cr2  1  0.828  0.172  0.191  1.0
  Cr  Cr3  1  0.656  0.828  0.691  1.0
  Cr  Cr4  1  0.172  0.344  0.691  1.0
  Cr  Cr5  1  0.828  0.656  0.191  1.0
  Cr  Cr6  1  0.344  0.172  0.191  1.0
  Cr  Cr7  1  0.172  0.828  0.691  1.0
  Cr  Cr8  1  0.000  0.000  0.442  1.0
  Cr  Cr9  1  0.000  0.000  0.942  1.0
  O  O10  1  0.856  0.144  0.017  1.0
  O  O11  1  0.711  0.856  0.517  1.0
  O  O12  1  0.144  0.289  0.517  1.0
  O  O13  1  0.856  0.711  0.017  1.0
  O  O14  1  0.289  0.144  0.017  1.0
  O  O15  1  0.144  0.856  0.517  1.0
  O  O16  1  0.000  0.000  0.745  1.0
  O  O17  1  0.000  0.000  0.245  1.0
  O  O18  1  0.527  0.473  0.256  1.0
  O  O19  1  0.055  0.527  0.756  1.0
  O  O20  1  0.473  0.945  0.756  1.0
  O  O21  1  0.527  0.055  0.256  1.0
  O  O22  1  0.473  0.527  0.756  1.0
  O  O23  1  0.945  0.473  0.256  1.0
[/CIF]
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