The material structure described by CaMn2O4 crystallizes in the monoclinic P2_1/c space group. Ca(1) is bonded in a 5-coordinate geometry to one O(1), one O(2), one O(3), and two equivalent O(4) atoms. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(1), one O(3), two equivalent O(2), and two equivalent O(4) atoms to form distorted MnO6 octahedra that share corners with two equivalent Mn(1)O6 octahedra, corners with three equivalent Mn(2)O5 square pyramids,  an edgeedge with one Mn(1)O6 octahedra, and edges with two equivalent Mn(2)O5 square pyramids. The corner-sharing octahedral tilt angles are 47°. In the second Mn site, Mn(2) is bonded to one O(2), one O(3), one O(4), and two equivalent O(1) atoms to form distorted MnO5 square pyramids that share corners with three equivalent Mn(1)O6 octahedra, corners with two equivalent Mn(2)O5 square pyramids, and edges with two equivalent Mn(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 49-82°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted rectangular see-saw-like geometry to one Ca(1), one Mn(1), and two equivalent Mn(2) atoms. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Ca(1), one Mn(2), and two equivalent Mn(1) atoms. In the third O site, O(3) is bonded in a distorted T-shaped geometry to one Ca(1), one Mn(1), and one Mn(2) atom. In the fourth O site, O(4) is bonded to two equivalent Ca(1), one Mn(2), and two equivalent Mn(1) atoms to form distorted edge-sharing OCa2Mn3 trigonal bipyramids. is represented by the CIF file [CIF]
data_CaMn2O4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.793
_cell_length_b   5.689
_cell_length_c   10.953
_cell_angle_alpha   87.921
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   360.755
_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  0.580  0.268  0.095  1.0
  Ca  Ca1  1  0.420  0.732  0.905  1.0
  Ca  Ca2  1  0.920  0.268  0.595  1.0
  Ca  Ca3  1  0.080  0.732  0.405  1.0
  Mn  Mn4  1  0.045  0.639  0.125  1.0
  Mn  Mn5  1  0.087  0.134  0.150  1.0
  Mn  Mn6  1  0.913  0.866  0.850  1.0
  Mn  Mn7  1  0.955  0.361  0.875  1.0
  Mn  Mn8  1  0.587  0.866  0.350  1.0
  Mn  Mn9  1  0.545  0.361  0.375  1.0
  Mn  Mn10  1  0.455  0.639  0.625  1.0
  Mn  Mn11  1  0.413  0.134  0.650  1.0
  O  O12  1  0.905  0.879  0.226  1.0
  O  O13  1  0.894  0.381  0.211  1.0
  O  O14  1  0.106  0.619  0.789  1.0
  O  O15  1  0.095  0.121  0.774  1.0
  O  O16  1  0.394  0.619  0.289  1.0
  O  O17  1  0.405  0.121  0.274  1.0
  O  O18  1  0.595  0.879  0.726  1.0
  O  O19  1  0.606  0.381  0.711  1.0
  O  O20  1  0.224  0.897  0.053  1.0
  O  O21  1  0.217  0.395  0.040  1.0
  O  O22  1  0.783  0.605  0.960  1.0
  O  O23  1  0.776  0.103  0.947  1.0
  O  O24  1  0.276  0.897  0.553  1.0
  O  O25  1  0.283  0.395  0.540  1.0
  O  O26  1  0.717  0.605  0.460  1.0
  O  O27  1  0.724  0.103  0.447  1.0
[/CIF]
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The material structure described by CaMn2O4 crystallizes in the monoclinic P2_1/c space group. Ca(1) is bonded in a 5-coordinate geometry to one O(1), one O(2), one O(3), and two equivalent O(4) atoms. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(1), one O(3), two equivalent O(2), and two equivalent O(4) atoms to form distorted MnO6 octahedra that share corners with two equivalent Mn(1)O6 octahedra, corners with three equivalent Mn(2)O5 square pyramids,  an edgeedge with one Mn(1)O6 octahedra, and edges with two equivalent Mn(2)O5 square pyramids. The corner-sharing octahedral tilt angles are 47°. In the second Mn site, Mn(2) is bonded to one O(2), one O(3), one O(4), and two equivalent O(1) atoms to form distorted MnO5 square pyramids that share corners with three equivalent Mn(1)O6 octahedra, corners with two equivalent Mn(2)O5 square pyramids, and edges with two equivalent Mn(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 49-82°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted rectangular see-saw-like geometry to one Ca(1), one Mn(1), and two equivalent Mn(2) atoms. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Ca(1), one Mn(2), and two equivalent Mn(1) atoms. In the third O site, O(3) is bonded in a distorted T-shaped geometry to one Ca(1), one Mn(1), and one Mn(2) atom. In the fourth O site, O(4) is bonded to two equivalent Ca(1), one Mn(2), and two equivalent Mn(1) atoms to form distorted edge-sharing OCa2Mn3 trigonal bipyramids. is represented by the CIF file [CIF]
data_CaMn2O4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.793
_cell_length_b   5.689
_cell_length_c   10.953
_cell_angle_alpha   87.921
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   360.755
_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  0.580  0.268  0.095  1.0
  Ca  Ca1  1  0.420  0.732  0.905  1.0
  Ca  Ca2  1  0.920  0.268  0.595  1.0
  Ca  Ca3  1  0.080  0.732  0.405  1.0
  Mn  Mn4  1  0.045  0.639  0.125  1.0
  Mn  Mn5  1  0.087  0.134  0.150  1.0
  Mn  Mn6  1  0.913  0.866  0.850  1.0
  Mn  Mn7  1  0.955  0.361  0.875  1.0
  Mn  Mn8  1  0.587  0.866  0.350  1.0
  Mn  Mn9  1  0.545  0.361  0.375  1.0
  Mn  Mn10  1  0.455  0.639  0.625  1.0
  Mn  Mn11  1  0.413  0.134  0.650  1.0
  O  O12  1  0.905  0.879  0.226  1.0
  O  O13  1  0.894  0.381  0.211  1.0
  O  O14  1  0.106  0.619  0.789  1.0
  O  O15  1  0.095  0.121  0.774  1.0
  O  O16  1  0.394  0.619  0.289  1.0
  O  O17  1  0.405  0.121  0.274  1.0
  O  O18  1  0.595  0.879  0.726  1.0
  O  O19  1  0.606  0.381  0.711  1.0
  O  O20  1  0.224  0.897  0.053  1.0
  O  O21  1  0.217  0.395  0.040  1.0
  O  O22  1  0.783  0.605  0.960  1.0
  O  O23  1  0.776  0.103  0.947  1.0
  O  O24  1  0.276  0.897  0.553  1.0
  O  O25  1  0.283  0.395  0.540  1.0
  O  O26  1  0.717  0.605  0.460  1.0
  O  O27  1  0.724  0.103  0.447  1.0
[/CIF]
.