The material structure described by Ca2MnO4 is (La,Ba)CuO4-like structured and crystallizes in the tetragonal I4_1/acd space group. Ca(1) is bonded in a 9-coordinate geometry to four equivalent O(2) and five equivalent O(1) atoms. Mn(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form corner-sharing MnO6 octahedra. The corner-sharing octahedral tilt angles are 19°. There are two inequivalent O sites. In the first O site, O(2) is bonded in a 4-coordinate geometry to four equivalent Ca(1) and two equivalent Mn(1) atoms. In the second O site, O(1) is bonded to five equivalent Ca(1) and one Mn(1) atom to form a mixture of corner and edge-sharing OCa5Mn octahedra. The corner-sharing octahedral tilt angles range from 0-7°. is represented by the CIF file [CIF]
data_Ca2MnO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.165
_cell_length_b   5.165
_cell_length_c   12.638
_cell_angle_alpha   78.207
_cell_angle_beta   78.207
_cell_angle_gamma   89.999
_symmetry_Int_Tables_number   1
_cell_volume   322.801
_cell_formula_units_Z   4
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
  Ca  Ca0  1  0.449  0.699  0.102  1.0
  Ca  Ca1  1  0.301  0.551  0.398  1.0
  Ca  Ca2  1  0.801  0.051  0.398  1.0
  Ca  Ca3  1  0.949  0.199  0.102  1.0
  Ca  Ca4  1  0.199  0.949  0.602  1.0
  Ca  Ca5  1  0.051  0.801  0.898  1.0
  Ca  Ca6  1  0.551  0.301  0.898  1.0
  Ca  Ca7  1  0.699  0.449  0.602  1.0
  Mn  Mn8  1  0.125  0.375  0.750  1.0
  Mn  Mn9  1  0.875  0.625  0.250  1.0
  Mn  Mn10  1  0.625  0.875  0.750  1.0
  Mn  Mn11  1  0.375  0.125  0.250  1.0
  O  O12  1  0.545  0.795  0.911  1.0
  O  O13  1  0.205  0.455  0.589  1.0
  O  O14  1  0.705  0.955  0.589  1.0
  O  O15  1  0.045  0.295  0.911  1.0
  O  O16  1  0.295  0.045  0.411  1.0
  O  O17  1  0.955  0.705  0.089  1.0
  O  O18  1  0.455  0.205  0.089  1.0
  O  O19  1  0.795  0.545  0.411  1.0
  O  O20  1  0.082  0.332  0.250  1.0
  O  O21  1  0.668  0.918  0.250  1.0
  O  O22  1  0.582  0.418  0.250  1.0
  O  O23  1  0.168  0.832  0.250  1.0
  O  O24  1  0.418  0.582  0.750  1.0
  O  O25  1  0.832  0.168  0.750  1.0
  O  O26  1  0.918  0.668  0.750  1.0
  O  O27  1  0.332  0.082  0.750  1.0
[/CIF]
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The material structure described by Ca2MnO4 is (La,Ba)CuO4-like structured and crystallizes in the tetragonal I4_1/acd space group. Ca(1) is bonded in a 9-coordinate geometry to four equivalent O(2) and five equivalent O(1) atoms. Mn(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form corner-sharing MnO6 octahedra. The corner-sharing octahedral tilt angles are 19°. There are two inequivalent O sites. In the first O site, O(2) is bonded in a 4-coordinate geometry to four equivalent Ca(1) and two equivalent Mn(1) atoms. In the second O site, O(1) is bonded to five equivalent Ca(1) and one Mn(1) atom to form a mixture of corner and edge-sharing OCa5Mn octahedra. The corner-sharing octahedral tilt angles range from 0-7°. is represented by the CIF file [CIF]
data_Ca2MnO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.165
_cell_length_b   5.165
_cell_length_c   12.638
_cell_angle_alpha   78.207
_cell_angle_beta   78.207
_cell_angle_gamma   89.999
_symmetry_Int_Tables_number   1
_cell_volume   322.801
_cell_formula_units_Z   4
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
  Ca  Ca0  1  0.449  0.699  0.102  1.0
  Ca  Ca1  1  0.301  0.551  0.398  1.0
  Ca  Ca2  1  0.801  0.051  0.398  1.0
  Ca  Ca3  1  0.949  0.199  0.102  1.0
  Ca  Ca4  1  0.199  0.949  0.602  1.0
  Ca  Ca5  1  0.051  0.801  0.898  1.0
  Ca  Ca6  1  0.551  0.301  0.898  1.0
  Ca  Ca7  1  0.699  0.449  0.602  1.0
  Mn  Mn8  1  0.125  0.375  0.750  1.0
  Mn  Mn9  1  0.875  0.625  0.250  1.0
  Mn  Mn10  1  0.625  0.875  0.750  1.0
  Mn  Mn11  1  0.375  0.125  0.250  1.0
  O  O12  1  0.545  0.795  0.911  1.0
  O  O13  1  0.205  0.455  0.589  1.0
  O  O14  1  0.705  0.955  0.589  1.0
  O  O15  1  0.045  0.295  0.911  1.0
  O  O16  1  0.295  0.045  0.411  1.0
  O  O17  1  0.955  0.705  0.089  1.0
  O  O18  1  0.455  0.205  0.089  1.0
  O  O19  1  0.795  0.545  0.411  1.0
  O  O20  1  0.082  0.332  0.250  1.0
  O  O21  1  0.668  0.918  0.250  1.0
  O  O22  1  0.582  0.418  0.250  1.0
  O  O23  1  0.168  0.832  0.250  1.0
  O  O24  1  0.418  0.582  0.750  1.0
  O  O25  1  0.832  0.168  0.750  1.0
  O  O26  1  0.918  0.668  0.750  1.0
  O  O27  1  0.332  0.082  0.750  1.0
[/CIF]
.