The structure described by Ba(MnO4)2 crystallizes in the orthorhombic Fddd space group. Ba(1) is bonded in a body-centered cubic geometry to four equivalent O(1) and four equivalent O(2) atoms. Mn(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form edge-sharing MnO6 octahedra. There are two inequivalent O sites. In the first O site, O(2) is bonded in a distorted L-shaped geometry to one Ba(1) and two equivalent Mn(1) atoms. In the second O site, O(1) is bonded in a distorted single-bond geometry to one Ba(1) and one Mn(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_BaMn2O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.884
_cell_length_b   8.456
_cell_length_c   7.915
_cell_angle_alpha   83.269
_cell_angle_beta   50.494
_cell_angle_gamma   46.237
_symmetry_Int_Tables_number   1
_cell_volume   330.844
_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  0.500  0.500  0.500  1.0
  Ba  Ba1  1  0.750  0.750  0.750  1.0
  Mn  Mn2  1  0.247  0.753  0.247  1.0
  Mn  Mn3  1  0.003  0.497  0.003  1.0
  Mn  Mn4  1  0.753  0.247  0.753  1.0
  Mn  Mn5  1  0.497  0.003  0.497  1.0
  O  O6  1  0.045  0.684  0.953  1.0
  O  O7  1  0.953  0.318  0.045  1.0
  O  O8  1  0.205  0.566  0.297  1.0
  O  O9  1  0.297  0.932  0.205  1.0
  O  O10  1  0.684  0.045  0.318  1.0
  O  O11  1  0.318  0.953  0.684  1.0
  O  O12  1  0.566  0.205  0.932  1.0
  O  O13  1  0.932  0.297  0.566  1.0
  O  O14  1  0.077  0.896  0.593  1.0
  O  O15  1  0.593  0.433  0.077  1.0
  O  O16  1  0.173  0.354  0.657  1.0
  O  O17  1  0.657  0.817  0.173  1.0
  O  O18  1  0.896  0.077  0.433  1.0
  O  O19  1  0.433  0.593  0.896  1.0
  O  O20  1  0.354  0.173  0.817  1.0
  O  O21  1  0.817  0.657  0.354  1.0
[/CIF]
.
The structure described by Ba(MnO4)2 crystallizes in the orthorhombic Fddd space group. Ba(1) is bonded in a body-centered cubic geometry to four equivalent O(1) and four equivalent O(2) atoms. Mn(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form edge-sharing MnO6 octahedra. There are two inequivalent O sites. In the first O site, O(2) is bonded in a distorted L-shaped geometry to one Ba(1) and two equivalent Mn(1) atoms. In the second O site, O(1) is bonded in a distorted single-bond geometry to one Ba(1) and one Mn(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_BaMn2O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.884
_cell_length_b   8.456
_cell_length_c   7.915
_cell_angle_alpha   83.269
_cell_angle_beta   50.494
_cell_angle_gamma   46.237
_symmetry_Int_Tables_number   1
_cell_volume   330.844
_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  0.500  0.500  0.500  1.0
  Ba  Ba1  1  0.750  0.750  0.750  1.0
  Mn  Mn2  1  0.247  0.753  0.247  1.0
  Mn  Mn3  1  0.003  0.497  0.003  1.0
  Mn  Mn4  1  0.753  0.247  0.753  1.0
  Mn  Mn5  1  0.497  0.003  0.497  1.0
  O  O6  1  0.045  0.684  0.953  1.0
  O  O7  1  0.953  0.318  0.045  1.0
  O  O8  1  0.205  0.566  0.297  1.0
  O  O9  1  0.297  0.932  0.205  1.0
  O  O10  1  0.684  0.045  0.318  1.0
  O  O11  1  0.318  0.953  0.684  1.0
  O  O12  1  0.566  0.205  0.932  1.0
  O  O13  1  0.932  0.297  0.566  1.0
  O  O14  1  0.077  0.896  0.593  1.0
  O  O15  1  0.593  0.433  0.077  1.0
  O  O16  1  0.173  0.354  0.657  1.0
  O  O17  1  0.657  0.817  0.173  1.0
  O  O18  1  0.896  0.077  0.433  1.0
  O  O19  1  0.433  0.593  0.896  1.0
  O  O20  1  0.354  0.173  0.817  1.0
  O  O21  1  0.817  0.657  0.354  1.0
[/CIF]
.