The material structure described by CaMn2O4 is Spinel-like structured and crystallizes in the monoclinic Cm space group. There are six inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to one O(1), one O(13), and two equivalent O(3) atoms to form CaO4 tetrahedra that share  a cornercorner with one Mn(8)O6 octahedra, corners with two equivalent Mn(2)O6 octahedra, corners with two equivalent Mn(6)O6 octahedra, corners with three equivalent Ca(3)O6 octahedra, and corners with four equivalent Mn(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 52-73°. In the second Ca site, Ca(2) is bonded to one O(2), one O(5), and two equivalent O(7) atoms to form CaO4 tetrahedra that share  a cornercorner with one Mn(2)O6 octahedra, corners with two equivalent Mn(1)O6 octahedra, corners with two equivalent Mn(5)O6 octahedra, corners with three equivalent Mn(4)O6 octahedra, and corners with four equivalent Mn(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 53-64°. In the third Ca site, Ca(3) is bonded to one O(1), one O(18), two equivalent O(16), and two equivalent O(3) atoms to form CaO6 octahedra that share corners with three equivalent Ca(1)O4 tetrahedra, corners with three equivalent Mn(9)O4 tetrahedra,  an edgeedge with one Mn(2)O6 octahedra,  an edgeedge with one Mn(8)O6 octahedra, edges with two equivalent Mn(1)O6 octahedra, and edges with two equivalent Mn(6)O6 octahedra. In the fourth Ca site, Ca(4) is bonded to one O(11), one O(8), and two equivalent O(14) atoms to form CaO4 tetrahedra that share  a cornercorner with one Mn(5)O6 octahedra, corners with two equivalent Mn(3)O6 octahedra, corners with two equivalent Mn(8)O6 octahedra, corners with three equivalent Mn(7)O6 octahedra, and corners with four equivalent Mn(6)O6 octahedra. The corner-sharing octahedral tilt angles range from 53-68°. In the fifth Ca site, Ca(5) is bonded to one O(12), one O(9), and two equivalent O(4) atoms to form CaO4 tetrahedra that share  a cornercorner with one Mn(5)O6 octahedra, corners with two equivalent Mn(2)O6 octahedra, corners with two equivalent Mn(3)O6 octahedra, corners with three equivalent Mn(4)O6 octahedra, and corners with four equivalent Mn(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 55-70°. In the sixth Ca site, Ca(6) is bonded to one O(15), one O(17), and two equivalent O(10) atoms to form CaO4 tetrahedra that share  a cornercorner with one Mn(8)O6 octahedra, corners with two equivalent Mn(5)O6 octahedra, corners with two equivalent Mn(6)O6 octahedra, corners with three equivalent Mn(7)O6 octahedra, and corners with four equivalent Mn(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 55-63°. There are nine inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(6), and one O(9) atom to form MnO6 octahedra that share  a cornercorner with one Ca(2)O4 tetrahedra,  a cornercorner with one Mn(9)O4 tetrahedra, corners with two equivalent Ca(1)O4 tetrahedra, corners with two equivalent Ca(5)O4 tetrahedra,  an edgeedge with one Ca(3)O6 octahedra,  an edgeedge with one Mn(4)O6 octahedra, edges with two equivalent Mn(1)O6 octahedra, and edges with two equivalent Mn(2)O6 octahedra. In the second Mn site, Mn(2) is bonded to one O(2), one O(6), two equivalent O(3), and two equivalent O(4) atoms to form distorted MnO6 octahedra that share  a cornercorner with one Ca(2)O4 tetrahedra,  a cornercorner with one Mn(9)O4 tetrahedra, corners with two equivalent Ca(1)O4 tetrahedra, corners with two equivalent Ca(5)O4 tetrahedra,  an edgeedge with one Ca(3)O6 octahedra,  an edgeedge with one Mn(4)O6 octahedra, and edges with four equivalent Mn(1)O6 octahedra. In the third Mn site, Mn(3) is bonded to one O(10), one O(12), one O(15), one O(5), one O(7), and one O(8) atom to form MnO6 octahedra that share  a cornercorner with one Ca(4)O4 tetrahedra,  a cornercorner with one Ca(5)O4 tetrahedra, corners with two equivalent Ca(2)O4 tetrahedra, corners with two equivalent Ca(6)O4 tetrahedra,  an edgeedge with one Mn(4)O6 octahedra,  an edgeedge with one Mn(7)O6 octahedra, edges with two equivalent Mn(3)O6 octahedra, and edges with two equivalent Mn(5)O6 octahedra. In the fourth Mn site, Mn(4) is bonded to one O(5), one O(9), two equivalent O(4), and two equivalent O(7) atoms to form distorted MnO6 octahedra that share corners with three equivalent Ca(2)O4 tetrahedra, corners with three equivalent Ca(5)O4 tetrahedra,  an edgeedge with one Mn(2)O6 octahedra,  an edgeedge with one Mn(5)O6 octahedra, edges with two equivalent Mn(1)O6 octahedra, and edges with two equivalent Mn(3)O6 octahedra. In the fifth Mn site, Mn(5) is bonded to one O(12), one O(8), two equivalent O(10), and two equivalent O(7) atoms to form distorted MnO6 octahedra that share  a cornercorner with one Ca(4)O4 tetrahedra,  a cornercorner with one Ca(5)O4 tetrahedra, corners with two equivalent Ca(2)O4 tetrahedra, corners with two equivalent Ca(6)O4 tetrahedra,  an edgeedge with one Mn(4)O6 octahedra,  an edgeedge with one Mn(7)O6 octahedra, and edges with four equivalent Mn(3)O6 octahedra. In the sixth Mn site, Mn(6) is bonded to one O(11), one O(13), one O(14), one O(16), one O(17), and one O(18) atom to form distorted MnO6 octahedra that share  a cornercorner with one Ca(1)O4 tetrahedra,  a cornercorner with one Ca(6)O4 tetrahedra, corners with two equivalent Ca(4)O4 tetrahedra, corners with two equivalent Mn(9)O4 tetrahedra,  an edgeedge with one Ca(3)O6 octahedra,  an edgeedge with one Mn(7)O6 octahedra, edges with two equivalent Mn(6)O6 octahedra, and edges with two equivalent Mn(8)O6 octahedra. In the seventh Mn site, Mn(7) is bonded to one O(11), one O(15), two equivalent O(10), and two equivalent O(14) atoms to form MnO6 octahedra that share corners with three equivalent Ca(4)O4 tetrahedra, corners with three equivalent Ca(6)O4 tetrahedra,  an edgeedge with one Mn(5)O6 octahedra,  an edgeedge with one Mn(8)O6 octahedra, edges with two equivalent Mn(3)O6 octahedra, and edges with two equivalent Mn(6)O6 octahedra. In the eighth Mn site, Mn(8) is bonded to one O(13), one O(17), two equivalent O(14), and two equivalent O(16) atoms to form distorted MnO6 octahedra that share  a cornercorner with one Ca(1)O4 tetrahedra,  a cornercorner with one Ca(6)O4 tetrahedra, corners with two equivalent Ca(4)O4 tetrahedra, corners with two equivalent Mn(9)O4 tetrahedra,  an edgeedge with one Ca(3)O6 octahedra,  an edgeedge with one Mn(7)O6 octahedra, and edges with four equivalent Mn(6)O6 octahedra. In the ninth Mn site, Mn(9) is bonded to one O(18), one O(6), and two equivalent O(16) atoms to form MnO4 tetrahedra that share  a cornercorner with one Mn(2)O6 octahedra, corners with two equivalent Mn(1)O6 octahedra, corners with two equivalent Mn(8)O6 octahedra, corners with three equivalent Ca(3)O6 octahedra, and corners with four equivalent Mn(6)O6 octahedra. The corner-sharing octahedral tilt angles range from 54-68°. There are eighteen inequivalent O sites. In the first O site, O(1) is bonded to one Ca(1), one Ca(3), and two equivalent Mn(1) atoms to form distorted OCa2Mn2 tetrahedra that share corners with two equivalent O(4)CaMn3 tetrahedra, corners with two equivalent O(9)CaMn3 tetrahedra, corners with two equivalent O(3)Ca2Mn2 trigonal pyramids, corners with two equivalent O(16)CaMn3 trigonal pyramids,  an edgeedge with one O(2)CaMn3 trigonal pyramid, and edges with two equivalent O(3)Ca2Mn2 trigonal pyramids. In the second O site, O(2) is bonded to one Ca(2), one Mn(2), and two equivalent Mn(1) atoms to form distorted OCaMn3 trigonal pyramids that share  a cornercorner with one O(5)CaMn3 tetrahedra, corners with two equivalent O(7)CaMn3 tetrahedra, corners with two equivalent O(9)CaMn3 tetrahedra, corners with four equivalent O(4)CaMn3 tetrahedra,  an edgeedge with one O(1)Ca2Mn2 tetrahedra, and edges with two equivalent O(3)Ca2Mn2 trigonal pyramids. In the third O site, O(3) is bonded to one Ca(1), one Ca(3), one Mn(1), and one Mn(2) atom to form distorted OCa2Mn2 trigonal pyramids that share  a cornercorner with one O(1)Ca2Mn2 tetrahedra,  a cornercorner with one O(9)CaMn3 tetrahedra, corners with three equivalent O(4)CaMn3 tetrahedra,  a cornercorner with one O(3)Ca2Mn2 trigonal pyramid, corners with two equivalent O(16)CaMn3 trigonal pyramids,  an edgeedge with one O(1)Ca2Mn2 tetrahedra,  an edgeedge with one O(3)Ca2Mn2 trigonal pyramid, and  an edgeedge with one O(2)CaMn3 trigonal pyramid. In the fourth O site, O(4) is bonded to one Ca(5), one Mn(1), one Mn(2), and one Mn(4) atom to form distorted OCaMn3 tetrahedra that share  a cornercorner with one O(1)Ca2Mn2 tetrahedra,  a cornercorner with one O(4)CaMn3 tetrahedra,  a cornercorner with one O(5)CaMn3 tetrahedra,  a cornercorner with one O(9)CaMn3 tetrahedra, corners with two equivalent O(7)CaMn3 tetrahedra, corners with two equivalent O(2)CaMn3 trigonal pyramids, corners with three equivalent O(3)Ca2Mn2 trigonal pyramids,  an edgeedge with one O(4)CaMn3 tetrahedra, and  an edgeedge with one O(9)CaMn3 tetrahedra. In the fifth O site, O(5) is bonded to one Ca(2), one Mn(4), and two equivalent Mn(3) atoms to form a mixture of distorted edge and corner-sharing OCaMn3 tetrahedra. In the sixth O site, O(6) is bonded in a distorted rectangular see-saw-like geometry to one Mn(2), one Mn(9), and two equivalent Mn(1) atoms. In the seventh O site, O(7) is bonded to one Ca(2), one Mn(3), one Mn(4), and one Mn(5) atom to form a mixture of distorted edge and corner-sharing OCaMn3 tetrahedra. In the eighth O site, O(8) is bonded to one Ca(4), one Mn(5), and two equivalent Mn(3) atoms to form a mixture of distorted edge and corner-sharing OCaMn3 trigonal pyramids. In the ninth O site, O(9) is bonded to one Ca(5), one Mn(4), and two equivalent Mn(1) atoms to form distorted OCaMn3 tetrahedra that share  a cornercorner with one O(5)CaMn3 tetrahedra, corners with two equivalent O(1)Ca2Mn2 tetrahedra, corners with two equivalent O(4)CaMn3 tetrahedra, corners with two equivalent O(7)CaMn3 tetrahedra, corners with two equivalent O(3)Ca2Mn2 trigonal pyramids, corners with two equivalent O(2)CaMn3 trigonal pyramids, and edges with two equivalent O(4)CaMn3 tetrahedra. In the tenth O site, O(10) is bonded to one Ca(6), one Mn(3), one Mn(5), and one Mn(7) atom to form a mixture of distorted edge and corner-sharing OCaMn3 tetrahedra. In the eleventh O site, O(11) is bonded to one Ca(4), one Mn(7), and two equivalent Mn(6) atoms to form a mixture of distorted edge and corner-sharing OCaMn3 tetrahedra. In the twelfth O site, O(12) is bonded in a 4-coordinate geometry to one Ca(5), one Mn(5), and two equivalent Mn(3) atoms. In the thirteenth O site, O(13) is bonded in a distorted rectangular see-saw-like geometry to one Ca(1), one Mn(8), and two equivalent Mn(6) atoms. In the fourteenth O site, O(14) is bonded to one Ca(4), one Mn(6), one Mn(7), and one Mn(8) atom to form a mixture of distorted edge and corner-sharing OCaMn3 tetrahedra. In the fifteenth O site, O(15) is bonded to one Ca(6), one Mn(7), and two equivalent Mn(3) atoms to form a mixture of distorted edge and corner-sharing OCaMn3 tetrahedra. In the sixteenth O site, O(16) is bonded to one Ca(3), one Mn(6), one Mn(8), and one Mn(9) atom to form distorted OCaMn3 trigonal pyramids that share  a cornercorner with one O(1)Ca2Mn2 tetrahedra,  a cornercorner with one O(11)CaMn3 tetrahedra, corners with three equivalent O(14)CaMn3 tetrahedra,  a cornercorner with one O(16)CaMn3 trigonal pyramid, corners with two equivalent O(3)Ca2Mn2 trigonal pyramids,  an edgeedge with one O(17)CaMn3 tetrahedra, and  an edgeedge with one O(16)CaMn3 trigonal pyramid. In the seventeenth O site, O(17) is bonded to one Ca(6), one Mn(8), and two equivalent Mn(6) atoms to form a mixture of distorted edge and corner-sharing OCaMn3 tetrahedra. In the eighteenth O site, O(18) is bonded in a rectangular see-saw-like geometry to one Ca(3), one Mn(9), and two equivalent Mn(6) atoms. is represented by the CIF file [CIF]
data_CaMn2O4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.565
_cell_length_b   6.565
_cell_length_c   15.549
_cell_angle_alpha   83.520
_cell_angle_beta   83.520
_cell_angle_gamma   54.378
_symmetry_Int_Tables_number   1
_cell_volume   540.291
_cell_formula_units_Z   6
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  0.171  0.171  0.954  1.0
  Ca  Ca1  1  0.502  0.502  0.621  1.0
  Ca  Ca2  1  0.498  0.498  0.000  1.0
  Ca  Ca3  1  0.836  0.836  0.283  1.0
  Ca  Ca4  1  0.167  0.167  0.715  1.0
  Ca  Ca5  1  0.496  0.496  0.376  1.0
  Mn  Mn6  1  0.171  0.674  0.833  1.0
  Mn  Mn7  1  0.669  0.669  0.825  1.0
  Mn  Mn8  1  0.499  0.998  0.500  1.0
  Mn  Mn9  1  0.674  0.171  0.833  1.0
  Mn  Mn10  1  0.838  0.838  0.664  1.0
  Mn  Mn11  1  0.998  0.998  0.499  1.0
  Mn  Mn12  1  0.835  0.331  0.168  1.0
  Mn  Mn13  1  0.998  0.499  0.500  1.0
  Mn  Mn14  1  0.331  0.835  0.168  1.0
  Mn  Mn15  1  0.162  0.162  0.337  1.0
  Mn  Mn16  1  0.325  0.325  0.173  1.0
  Mn  Mn17  1  0.830  0.830  0.049  1.0
  O  O18  1  0.358  0.358  0.904  1.0
  O  O19  1  0.495  0.495  0.762  1.0
  O  O20  1  0.353  0.814  0.891  1.0
  O  O21  1  0.814  0.353  0.891  1.0
  O  O22  1  0.557  0.982  0.753  1.0
  O  O23  1  0.691  0.691  0.577  1.0
  O  O24  1  0.982  0.557  0.753  1.0
  O  O25  1  0.849  0.849  0.910  1.0
  O  O26  1  0.695  0.121  0.577  1.0
  O  O27  1  0.824  0.824  0.430  1.0
  O  O28  1  0.976  0.976  0.756  1.0
  O  O29  1  0.121  0.695  0.577  1.0
  O  O30  1  0.874  0.303  0.424  1.0
  O  O31  1  0.025  0.025  0.246  1.0
  O  O32  1  0.303  0.874  0.424  1.0
  O  O33  1  0.174  0.174  0.570  1.0
  O  O34  1  0.156  0.156  0.100  1.0
  O  O35  1  0.022  0.445  0.251  1.0
  O  O36  1  0.308  0.308  0.424  1.0
  O  O37  1  0.445  0.022  0.251  1.0
  O  O38  1  0.168  0.645  0.103  1.0
  O  O39  1  0.506  0.506  0.233  1.0
  O  O40  1  0.645  0.168  0.103  1.0
  O  O41  1  0.651  0.651  0.092  1.0
[/CIF]
.
The material structure described by CaMn2O4 is Spinel-like structured and crystallizes in the monoclinic Cm space group. There are six inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to one O(1), one O(13), and two equivalent O(3) atoms to form CaO4 tetrahedra that share  a cornercorner with one Mn(8)O6 octahedra, corners with two equivalent Mn(2)O6 octahedra, corners with two equivalent Mn(6)O6 octahedra, corners with three equivalent Ca(3)O6 octahedra, and corners with four equivalent Mn(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 52-73°. In the second Ca site, Ca(2) is bonded to one O(2), one O(5), and two equivalent O(7) atoms to form CaO4 tetrahedra that share  a cornercorner with one Mn(2)O6 octahedra, corners with two equivalent Mn(1)O6 octahedra, corners with two equivalent Mn(5)O6 octahedra, corners with three equivalent Mn(4)O6 octahedra, and corners with four equivalent Mn(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 53-64°. In the third Ca site, Ca(3) is bonded to one O(1), one O(18), two equivalent O(16), and two equivalent O(3) atoms to form CaO6 octahedra that share corners with three equivalent Ca(1)O4 tetrahedra, corners with three equivalent Mn(9)O4 tetrahedra,  an edgeedge with one Mn(2)O6 octahedra,  an edgeedge with one Mn(8)O6 octahedra, edges with two equivalent Mn(1)O6 octahedra, and edges with two equivalent Mn(6)O6 octahedra. In the fourth Ca site, Ca(4) is bonded to one O(11), one O(8), and two equivalent O(14) atoms to form CaO4 tetrahedra that share  a cornercorner with one Mn(5)O6 octahedra, corners with two equivalent Mn(3)O6 octahedra, corners with two equivalent Mn(8)O6 octahedra, corners with three equivalent Mn(7)O6 octahedra, and corners with four equivalent Mn(6)O6 octahedra. The corner-sharing octahedral tilt angles range from 53-68°. In the fifth Ca site, Ca(5) is bonded to one O(12), one O(9), and two equivalent O(4) atoms to form CaO4 tetrahedra that share  a cornercorner with one Mn(5)O6 octahedra, corners with two equivalent Mn(2)O6 octahedra, corners with two equivalent Mn(3)O6 octahedra, corners with three equivalent Mn(4)O6 octahedra, and corners with four equivalent Mn(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 55-70°. In the sixth Ca site, Ca(6) is bonded to one O(15), one O(17), and two equivalent O(10) atoms to form CaO4 tetrahedra that share  a cornercorner with one Mn(8)O6 octahedra, corners with two equivalent Mn(5)O6 octahedra, corners with two equivalent Mn(6)O6 octahedra, corners with three equivalent Mn(7)O6 octahedra, and corners with four equivalent Mn(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 55-63°. There are nine inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(6), and one O(9) atom to form MnO6 octahedra that share  a cornercorner with one Ca(2)O4 tetrahedra,  a cornercorner with one Mn(9)O4 tetrahedra, corners with two equivalent Ca(1)O4 tetrahedra, corners with two equivalent Ca(5)O4 tetrahedra,  an edgeedge with one Ca(3)O6 octahedra,  an edgeedge with one Mn(4)O6 octahedra, edges with two equivalent Mn(1)O6 octahedra, and edges with two equivalent Mn(2)O6 octahedra. In the second Mn site, Mn(2) is bonded to one O(2), one O(6), two equivalent O(3), and two equivalent O(4) atoms to form distorted MnO6 octahedra that share  a cornercorner with one Ca(2)O4 tetrahedra,  a cornercorner with one Mn(9)O4 tetrahedra, corners with two equivalent Ca(1)O4 tetrahedra, corners with two equivalent Ca(5)O4 tetrahedra,  an edgeedge with one Ca(3)O6 octahedra,  an edgeedge with one Mn(4)O6 octahedra, and edges with four equivalent Mn(1)O6 octahedra. In the third Mn site, Mn(3) is bonded to one O(10), one O(12), one O(15), one O(5), one O(7), and one O(8) atom to form MnO6 octahedra that share  a cornercorner with one Ca(4)O4 tetrahedra,  a cornercorner with one Ca(5)O4 tetrahedra, corners with two equivalent Ca(2)O4 tetrahedra, corners with two equivalent Ca(6)O4 tetrahedra,  an edgeedge with one Mn(4)O6 octahedra,  an edgeedge with one Mn(7)O6 octahedra, edges with two equivalent Mn(3)O6 octahedra, and edges with two equivalent Mn(5)O6 octahedra. In the fourth Mn site, Mn(4) is bonded to one O(5), one O(9), two equivalent O(4), and two equivalent O(7) atoms to form distorted MnO6 octahedra that share corners with three equivalent Ca(2)O4 tetrahedra, corners with three equivalent Ca(5)O4 tetrahedra,  an edgeedge with one Mn(2)O6 octahedra,  an edgeedge with one Mn(5)O6 octahedra, edges with two equivalent Mn(1)O6 octahedra, and edges with two equivalent Mn(3)O6 octahedra. In the fifth Mn site, Mn(5) is bonded to one O(12), one O(8), two equivalent O(10), and two equivalent O(7) atoms to form distorted MnO6 octahedra that share  a cornercorner with one Ca(4)O4 tetrahedra,  a cornercorner with one Ca(5)O4 tetrahedra, corners with two equivalent Ca(2)O4 tetrahedra, corners with two equivalent Ca(6)O4 tetrahedra,  an edgeedge with one Mn(4)O6 octahedra,  an edgeedge with one Mn(7)O6 octahedra, and edges with four equivalent Mn(3)O6 octahedra. In the sixth Mn site, Mn(6) is bonded to one O(11), one O(13), one O(14), one O(16), one O(17), and one O(18) atom to form distorted MnO6 octahedra that share  a cornercorner with one Ca(1)O4 tetrahedra,  a cornercorner with one Ca(6)O4 tetrahedra, corners with two equivalent Ca(4)O4 tetrahedra, corners with two equivalent Mn(9)O4 tetrahedra,  an edgeedge with one Ca(3)O6 octahedra,  an edgeedge with one Mn(7)O6 octahedra, edges with two equivalent Mn(6)O6 octahedra, and edges with two equivalent Mn(8)O6 octahedra. In the seventh Mn site, Mn(7) is bonded to one O(11), one O(15), two equivalent O(10), and two equivalent O(14) atoms to form MnO6 octahedra that share corners with three equivalent Ca(4)O4 tetrahedra, corners with three equivalent Ca(6)O4 tetrahedra,  an edgeedge with one Mn(5)O6 octahedra,  an edgeedge with one Mn(8)O6 octahedra, edges with two equivalent Mn(3)O6 octahedra, and edges with two equivalent Mn(6)O6 octahedra. In the eighth Mn site, Mn(8) is bonded to one O(13), one O(17), two equivalent O(14), and two equivalent O(16) atoms to form distorted MnO6 octahedra that share  a cornercorner with one Ca(1)O4 tetrahedra,  a cornercorner with one Ca(6)O4 tetrahedra, corners with two equivalent Ca(4)O4 tetrahedra, corners with two equivalent Mn(9)O4 tetrahedra,  an edgeedge with one Ca(3)O6 octahedra,  an edgeedge with one Mn(7)O6 octahedra, and edges with four equivalent Mn(6)O6 octahedra. In the ninth Mn site, Mn(9) is bonded to one O(18), one O(6), and two equivalent O(16) atoms to form MnO4 tetrahedra that share  a cornercorner with one Mn(2)O6 octahedra, corners with two equivalent Mn(1)O6 octahedra, corners with two equivalent Mn(8)O6 octahedra, corners with three equivalent Ca(3)O6 octahedra, and corners with four equivalent Mn(6)O6 octahedra. The corner-sharing octahedral tilt angles range from 54-68°. There are eighteen inequivalent O sites. In the first O site, O(1) is bonded to one Ca(1), one Ca(3), and two equivalent Mn(1) atoms to form distorted OCa2Mn2 tetrahedra that share corners with two equivalent O(4)CaMn3 tetrahedra, corners with two equivalent O(9)CaMn3 tetrahedra, corners with two equivalent O(3)Ca2Mn2 trigonal pyramids, corners with two equivalent O(16)CaMn3 trigonal pyramids,  an edgeedge with one O(2)CaMn3 trigonal pyramid, and edges with two equivalent O(3)Ca2Mn2 trigonal pyramids. In the second O site, O(2) is bonded to one Ca(2), one Mn(2), and two equivalent Mn(1) atoms to form distorted OCaMn3 trigonal pyramids that share  a cornercorner with one O(5)CaMn3 tetrahedra, corners with two equivalent O(7)CaMn3 tetrahedra, corners with two equivalent O(9)CaMn3 tetrahedra, corners with four equivalent O(4)CaMn3 tetrahedra,  an edgeedge with one O(1)Ca2Mn2 tetrahedra, and edges with two equivalent O(3)Ca2Mn2 trigonal pyramids. In the third O site, O(3) is bonded to one Ca(1), one Ca(3), one Mn(1), and one Mn(2) atom to form distorted OCa2Mn2 trigonal pyramids that share  a cornercorner with one O(1)Ca2Mn2 tetrahedra,  a cornercorner with one O(9)CaMn3 tetrahedra, corners with three equivalent O(4)CaMn3 tetrahedra,  a cornercorner with one O(3)Ca2Mn2 trigonal pyramid, corners with two equivalent O(16)CaMn3 trigonal pyramids,  an edgeedge with one O(1)Ca2Mn2 tetrahedra,  an edgeedge with one O(3)Ca2Mn2 trigonal pyramid, and  an edgeedge with one O(2)CaMn3 trigonal pyramid. In the fourth O site, O(4) is bonded to one Ca(5), one Mn(1), one Mn(2), and one Mn(4) atom to form distorted OCaMn3 tetrahedra that share  a cornercorner with one O(1)Ca2Mn2 tetrahedra,  a cornercorner with one O(4)CaMn3 tetrahedra,  a cornercorner with one O(5)CaMn3 tetrahedra,  a cornercorner with one O(9)CaMn3 tetrahedra, corners with two equivalent O(7)CaMn3 tetrahedra, corners with two equivalent O(2)CaMn3 trigonal pyramids, corners with three equivalent O(3)Ca2Mn2 trigonal pyramids,  an edgeedge with one O(4)CaMn3 tetrahedra, and  an edgeedge with one O(9)CaMn3 tetrahedra. In the fifth O site, O(5) is bonded to one Ca(2), one Mn(4), and two equivalent Mn(3) atoms to form a mixture of distorted edge and corner-sharing OCaMn3 tetrahedra. In the sixth O site, O(6) is bonded in a distorted rectangular see-saw-like geometry to one Mn(2), one Mn(9), and two equivalent Mn(1) atoms. In the seventh O site, O(7) is bonded to one Ca(2), one Mn(3), one Mn(4), and one Mn(5) atom to form a mixture of distorted edge and corner-sharing OCaMn3 tetrahedra. In the eighth O site, O(8) is bonded to one Ca(4), one Mn(5), and two equivalent Mn(3) atoms to form a mixture of distorted edge and corner-sharing OCaMn3 trigonal pyramids. In the ninth O site, O(9) is bonded to one Ca(5), one Mn(4), and two equivalent Mn(1) atoms to form distorted OCaMn3 tetrahedra that share  a cornercorner with one O(5)CaMn3 tetrahedra, corners with two equivalent O(1)Ca2Mn2 tetrahedra, corners with two equivalent O(4)CaMn3 tetrahedra, corners with two equivalent O(7)CaMn3 tetrahedra, corners with two equivalent O(3)Ca2Mn2 trigonal pyramids, corners with two equivalent O(2)CaMn3 trigonal pyramids, and edges with two equivalent O(4)CaMn3 tetrahedra. In the tenth O site, O(10) is bonded to one Ca(6), one Mn(3), one Mn(5), and one Mn(7) atom to form a mixture of distorted edge and corner-sharing OCaMn3 tetrahedra. In the eleventh O site, O(11) is bonded to one Ca(4), one Mn(7), and two equivalent Mn(6) atoms to form a mixture of distorted edge and corner-sharing OCaMn3 tetrahedra. In the twelfth O site, O(12) is bonded in a 4-coordinate geometry to one Ca(5), one Mn(5), and two equivalent Mn(3) atoms. In the thirteenth O site, O(13) is bonded in a distorted rectangular see-saw-like geometry to one Ca(1), one Mn(8), and two equivalent Mn(6) atoms. In the fourteenth O site, O(14) is bonded to one Ca(4), one Mn(6), one Mn(7), and one Mn(8) atom to form a mixture of distorted edge and corner-sharing OCaMn3 tetrahedra. In the fifteenth O site, O(15) is bonded to one Ca(6), one Mn(7), and two equivalent Mn(3) atoms to form a mixture of distorted edge and corner-sharing OCaMn3 tetrahedra. In the sixteenth O site, O(16) is bonded to one Ca(3), one Mn(6), one Mn(8), and one Mn(9) atom to form distorted OCaMn3 trigonal pyramids that share  a cornercorner with one O(1)Ca2Mn2 tetrahedra,  a cornercorner with one O(11)CaMn3 tetrahedra, corners with three equivalent O(14)CaMn3 tetrahedra,  a cornercorner with one O(16)CaMn3 trigonal pyramid, corners with two equivalent O(3)Ca2Mn2 trigonal pyramids,  an edgeedge with one O(17)CaMn3 tetrahedra, and  an edgeedge with one O(16)CaMn3 trigonal pyramid. In the seventeenth O site, O(17) is bonded to one Ca(6), one Mn(8), and two equivalent Mn(6) atoms to form a mixture of distorted edge and corner-sharing OCaMn3 tetrahedra. In the eighteenth O site, O(18) is bonded in a rectangular see-saw-like geometry to one Ca(3), one Mn(9), and two equivalent Mn(6) atoms. is represented by the CIF file [CIF]
data_CaMn2O4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.565
_cell_length_b   6.565
_cell_length_c   15.549
_cell_angle_alpha   83.520
_cell_angle_beta   83.520
_cell_angle_gamma   54.378
_symmetry_Int_Tables_number   1
_cell_volume   540.291
_cell_formula_units_Z   6
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  0.171  0.171  0.954  1.0
  Ca  Ca1  1  0.502  0.502  0.621  1.0
  Ca  Ca2  1  0.498  0.498  0.000  1.0
  Ca  Ca3  1  0.836  0.836  0.283  1.0
  Ca  Ca4  1  0.167  0.167  0.715  1.0
  Ca  Ca5  1  0.496  0.496  0.376  1.0
  Mn  Mn6  1  0.171  0.674  0.833  1.0
  Mn  Mn7  1  0.669  0.669  0.825  1.0
  Mn  Mn8  1  0.499  0.998  0.500  1.0
  Mn  Mn9  1  0.674  0.171  0.833  1.0
  Mn  Mn10  1  0.838  0.838  0.664  1.0
  Mn  Mn11  1  0.998  0.998  0.499  1.0
  Mn  Mn12  1  0.835  0.331  0.168  1.0
  Mn  Mn13  1  0.998  0.499  0.500  1.0
  Mn  Mn14  1  0.331  0.835  0.168  1.0
  Mn  Mn15  1  0.162  0.162  0.337  1.0
  Mn  Mn16  1  0.325  0.325  0.173  1.0
  Mn  Mn17  1  0.830  0.830  0.049  1.0
  O  O18  1  0.358  0.358  0.904  1.0
  O  O19  1  0.495  0.495  0.762  1.0
  O  O20  1  0.353  0.814  0.891  1.0
  O  O21  1  0.814  0.353  0.891  1.0
  O  O22  1  0.557  0.982  0.753  1.0
  O  O23  1  0.691  0.691  0.577  1.0
  O  O24  1  0.982  0.557  0.753  1.0
  O  O25  1  0.849  0.849  0.910  1.0
  O  O26  1  0.695  0.121  0.577  1.0
  O  O27  1  0.824  0.824  0.430  1.0
  O  O28  1  0.976  0.976  0.756  1.0
  O  O29  1  0.121  0.695  0.577  1.0
  O  O30  1  0.874  0.303  0.424  1.0
  O  O31  1  0.025  0.025  0.246  1.0
  O  O32  1  0.303  0.874  0.424  1.0
  O  O33  1  0.174  0.174  0.570  1.0
  O  O34  1  0.156  0.156  0.100  1.0
  O  O35  1  0.022  0.445  0.251  1.0
  O  O36  1  0.308  0.308  0.424  1.0
  O  O37  1  0.445  0.022  0.251  1.0
  O  O38  1  0.168  0.645  0.103  1.0
  O  O39  1  0.506  0.506  0.233  1.0
  O  O40  1  0.645  0.168  0.103  1.0
  O  O41  1  0.651  0.651  0.092  1.0
[/CIF]
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