The material described by CaMn2O4 crystallizes in the monoclinic Cm space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 6-coordinate geometry to one O(2), one O(4), two equivalent O(6), and two equivalent O(7) atoms. In the second Ca site, Ca(2) is bonded in a 5-coordinate geometry to one O(3), two equivalent O(5), and two equivalent O(8) atoms. There are four inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(2), two equivalent O(4), and two equivalent O(5) atoms to form MnO5 square pyramids that share corners with two equivalent Mn(2)O6 octahedra, corners with two equivalent Mn(3)O6 octahedra, and edges with two equivalent Mn(1)O5 square pyramids. The corner-sharing octahedral tilt angles range from 52-58°. In the second Mn site, Mn(2) is bonded to one O(4), one O(8), two equivalent O(3), and two equivalent O(6) atoms to form distorted MnO6 octahedra that share corners with two equivalent Mn(1)O5 square pyramids, corners with two equivalent Mn(4)O5 square pyramids, edges with two equivalent Mn(2)O6 octahedra, and edges with two equivalent Mn(3)O6 octahedra. In the third Mn site, Mn(3) is bonded to one O(1), one O(6), two equivalent O(2), and two equivalent O(8) atoms to form distorted MnO6 octahedra that share corners with two equivalent Mn(1)O5 square pyramids, corners with two equivalent Mn(4)O5 square pyramids, edges with two equivalent Mn(2)O6 octahedra, and edges with two equivalent Mn(3)O6 octahedra. In the fourth Mn site, Mn(4) is bonded to one O(3), two equivalent O(1), and two equivalent O(7) atoms to form MnO5 square pyramids that share corners with two equivalent Mn(2)O6 octahedra, corners with two equivalent Mn(3)O6 octahedra, and edges with two equivalent Mn(4)O5 square pyramids. The corner-sharing octahedral tilt angles range from 50-60°. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Mn(3) and two equivalent Mn(4) atoms. In the second O site, O(2) is bonded to one Ca(1), one Mn(1), and two equivalent Mn(3) atoms to form distorted OCaMn3 tetrahedra that share corners with two equivalent O(8)Ca2Mn3 square pyramids, corners with two equivalent O(2)CaMn3 tetrahedra,  an edgeedge with one O(8)Ca2Mn3 square pyramid, and edges with two equivalent O(6)Ca2Mn3 square pyramids. In the third O site, O(3) is bonded to one Ca(2), one Mn(4), and two equivalent Mn(2) atoms to form distorted OCaMn3 tetrahedra that share corners with two equivalent O(6)Ca2Mn3 square pyramids, corners with two equivalent O(3)CaMn3 tetrahedra,  an edgeedge with one O(6)Ca2Mn3 square pyramid, and edges with two equivalent O(8)Ca2Mn3 square pyramids. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Ca(1), one Mn(2), and two equivalent Mn(1) atoms. In the fifth O site, O(5) is bonded in a rectangular see-saw-like geometry to two equivalent Ca(2) and two equivalent Mn(1) atoms. In the sixth O site, O(6) is bonded to two equivalent Ca(1), one Mn(3), and two equivalent Mn(2) atoms to form distorted OCa2Mn3 square pyramids that share corners with two equivalent O(3)CaMn3 tetrahedra, edges with two equivalent O(6)Ca2Mn3 square pyramids, edges with two equivalent O(8)Ca2Mn3 square pyramids,  an edgeedge with one O(3)CaMn3 tetrahedra, and edges with two equivalent O(2)CaMn3 tetrahedra. In the seventh O site, O(7) is bonded in a rectangular see-saw-like geometry to two equivalent Ca(1) and two equivalent Mn(4) atoms. In the eighth O site, O(8) is bonded to two equivalent Ca(2), one Mn(2), and two equivalent Mn(3) atoms to form OCa2Mn3 square pyramids that share corners with two equivalent O(2)CaMn3 tetrahedra, edges with two equivalent O(6)Ca2Mn3 square pyramids, edges with two equivalent O(8)Ca2Mn3 square pyramids,  an edgeedge with one O(2)CaMn3 tetrahedra, and edges with two equivalent O(3)CaMn3 tetrahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_CaMn2O4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.635
_cell_length_b   7.635
_cell_length_c   9.392
_cell_angle_alpha   59.618
_cell_angle_beta   59.618
_cell_angle_gamma   22.541
_symmetry_Int_Tables_number   1
_cell_volume   179.799
_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
  Ca  Ca0  1  0.663  0.663  0.838  1.0
  Ca  Ca1  1  0.353  0.353  0.179  1.0
  Mn  Mn2  1  0.405  0.405  0.815  1.0
  Mn  Mn3  1  0.853  0.853  0.498  1.0
  Mn  Mn4  1  0.151  0.151  0.518  1.0
  Mn  Mn5  1  0.598  0.598  0.211  1.0
  O  O6  1  0.113  0.113  0.330  1.0
  O  O7  1  0.572  0.572  0.670  1.0
  O  O8  1  0.431  0.431  0.345  1.0
  O  O9  1  0.868  0.868  0.720  1.0
  O  O10  1  0.898  0.898  0.967  1.0
  O  O11  1  0.254  0.254  0.628  1.0
  O  O12  1  0.118  0.118  0.050  1.0
  O  O13  1  0.750  0.750  0.380  1.0
[/CIF]
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The material described by CaMn2O4 crystallizes in the monoclinic Cm space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 6-coordinate geometry to one O(2), one O(4), two equivalent O(6), and two equivalent O(7) atoms. In the second Ca site, Ca(2) is bonded in a 5-coordinate geometry to one O(3), two equivalent O(5), and two equivalent O(8) atoms. There are four inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(2), two equivalent O(4), and two equivalent O(5) atoms to form MnO5 square pyramids that share corners with two equivalent Mn(2)O6 octahedra, corners with two equivalent Mn(3)O6 octahedra, and edges with two equivalent Mn(1)O5 square pyramids. The corner-sharing octahedral tilt angles range from 52-58°. In the second Mn site, Mn(2) is bonded to one O(4), one O(8), two equivalent O(3), and two equivalent O(6) atoms to form distorted MnO6 octahedra that share corners with two equivalent Mn(1)O5 square pyramids, corners with two equivalent Mn(4)O5 square pyramids, edges with two equivalent Mn(2)O6 octahedra, and edges with two equivalent Mn(3)O6 octahedra. In the third Mn site, Mn(3) is bonded to one O(1), one O(6), two equivalent O(2), and two equivalent O(8) atoms to form distorted MnO6 octahedra that share corners with two equivalent Mn(1)O5 square pyramids, corners with two equivalent Mn(4)O5 square pyramids, edges with two equivalent Mn(2)O6 octahedra, and edges with two equivalent Mn(3)O6 octahedra. In the fourth Mn site, Mn(4) is bonded to one O(3), two equivalent O(1), and two equivalent O(7) atoms to form MnO5 square pyramids that share corners with two equivalent Mn(2)O6 octahedra, corners with two equivalent Mn(3)O6 octahedra, and edges with two equivalent Mn(4)O5 square pyramids. The corner-sharing octahedral tilt angles range from 50-60°. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Mn(3) and two equivalent Mn(4) atoms. In the second O site, O(2) is bonded to one Ca(1), one Mn(1), and two equivalent Mn(3) atoms to form distorted OCaMn3 tetrahedra that share corners with two equivalent O(8)Ca2Mn3 square pyramids, corners with two equivalent O(2)CaMn3 tetrahedra,  an edgeedge with one O(8)Ca2Mn3 square pyramid, and edges with two equivalent O(6)Ca2Mn3 square pyramids. In the third O site, O(3) is bonded to one Ca(2), one Mn(4), and two equivalent Mn(2) atoms to form distorted OCaMn3 tetrahedra that share corners with two equivalent O(6)Ca2Mn3 square pyramids, corners with two equivalent O(3)CaMn3 tetrahedra,  an edgeedge with one O(6)Ca2Mn3 square pyramid, and edges with two equivalent O(8)Ca2Mn3 square pyramids. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Ca(1), one Mn(2), and two equivalent Mn(1) atoms. In the fifth O site, O(5) is bonded in a rectangular see-saw-like geometry to two equivalent Ca(2) and two equivalent Mn(1) atoms. In the sixth O site, O(6) is bonded to two equivalent Ca(1), one Mn(3), and two equivalent Mn(2) atoms to form distorted OCa2Mn3 square pyramids that share corners with two equivalent O(3)CaMn3 tetrahedra, edges with two equivalent O(6)Ca2Mn3 square pyramids, edges with two equivalent O(8)Ca2Mn3 square pyramids,  an edgeedge with one O(3)CaMn3 tetrahedra, and edges with two equivalent O(2)CaMn3 tetrahedra. In the seventh O site, O(7) is bonded in a rectangular see-saw-like geometry to two equivalent Ca(1) and two equivalent Mn(4) atoms. In the eighth O site, O(8) is bonded to two equivalent Ca(2), one Mn(2), and two equivalent Mn(3) atoms to form OCa2Mn3 square pyramids that share corners with two equivalent O(2)CaMn3 tetrahedra, edges with two equivalent O(6)Ca2Mn3 square pyramids, edges with two equivalent O(8)Ca2Mn3 square pyramids,  an edgeedge with one O(2)CaMn3 tetrahedra, and edges with two equivalent O(3)CaMn3 tetrahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_CaMn2O4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.635
_cell_length_b   7.635
_cell_length_c   9.392
_cell_angle_alpha   59.618
_cell_angle_beta   59.618
_cell_angle_gamma   22.541
_symmetry_Int_Tables_number   1
_cell_volume   179.799
_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
  Ca  Ca0  1  0.663  0.663  0.838  1.0
  Ca  Ca1  1  0.353  0.353  0.179  1.0
  Mn  Mn2  1  0.405  0.405  0.815  1.0
  Mn  Mn3  1  0.853  0.853  0.498  1.0
  Mn  Mn4  1  0.151  0.151  0.518  1.0
  Mn  Mn5  1  0.598  0.598  0.211  1.0
  O  O6  1  0.113  0.113  0.330  1.0
  O  O7  1  0.572  0.572  0.670  1.0
  O  O8  1  0.431  0.431  0.345  1.0
  O  O9  1  0.868  0.868  0.720  1.0
  O  O10  1  0.898  0.898  0.967  1.0
  O  O11  1  0.254  0.254  0.628  1.0
  O  O12  1  0.118  0.118  0.050  1.0
  O  O13  1  0.750  0.750  0.380  1.0
[/CIF]
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