The structure described by Ca4Mn4O11 crystallizes in the tetragonal P4/mmm space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a distorted q6 geometry to two equivalent O(2) and eight equivalent O(4) atoms. In the second Ca site, Ca(2) is bonded to two equivalent O(1), two equivalent O(3), and eight equivalent O(4) atoms to form CaO12 cuboctahedra that share corners with four equivalent Ca(2)O12 cuboctahedra, faces with four equivalent Ca(2)O12 cuboctahedra, faces with four equivalent Mn(2)O6 octahedra, and faces with four equivalent Mn(1)O5 square pyramids. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(1) and four equivalent O(4) atoms to form MnO5 square pyramids that share corners with four equivalent Mn(2)O6 octahedra,  a cornercorner with one Mn(1)O5 square pyramid, and faces with four equivalent Ca(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles are 10°. In the second Mn site, Mn(2) is bonded to one O(2), one O(3), and four equivalent O(4) atoms to form MnO6 octahedra that share corners with two equivalent Mn(2)O6 octahedra, corners with four equivalent Mn(1)O5 square pyramids, and faces with four equivalent Ca(2)O12 cuboctahedra. The corner-sharing octahedra are not tilted. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted linear geometry to four equivalent Ca(2) and two equivalent Mn(1) atoms. In the second O site, O(2) is bonded in a linear geometry to four equivalent Ca(1) and two equivalent Mn(2) atoms. In the third O site, O(3) is bonded to four equivalent Ca(2) and two equivalent Mn(2) atoms to form distorted corner-sharing OCa4Mn2 octahedra. The corner-sharing octahedra are not tilted. In the fourth O site, O(4) is bonded in a 6-coordinate geometry to two equivalent Ca(1), two equivalent Ca(2), one Mn(1), and one Mn(2) atom. is represented by the CIF file [CIF]
data_Ca4Mn4O11
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.432
_cell_length_b   5.432
_cell_length_c   7.634
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   225.249
_cell_formula_units_Z   1
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  0.500  0.000  0.750  1.0
  Ca  Ca1  1  0.500  0.000  0.250  1.0
  Ca  Ca2  1  0.000  0.500  0.750  1.0
  Ca  Ca3  1  0.000  0.500  0.250  1.0
  Mn  Mn4  1  0.000  0.000  0.006  1.0
  Mn  Mn5  1  0.000  0.000  0.494  1.0
  Mn  Mn6  1  0.500  0.500  0.993  1.0
  Mn  Mn7  1  0.500  0.500  0.507  1.0
  O  O8  1  0.000  0.000  0.250  1.0
  O  O9  1  0.500  0.500  0.750  1.0
  O  O10  1  0.500  0.500  0.250  1.0
  O  O11  1  0.755  0.755  0.977  1.0
  O  O12  1  0.755  0.755  0.523  1.0
  O  O13  1  0.245  0.245  0.977  1.0
  O  O14  1  0.245  0.245  0.523  1.0
  O  O15  1  0.755  0.245  0.977  1.0
  O  O16  1  0.755  0.245  0.523  1.0
  O  O17  1  0.245  0.755  0.977  1.0
  O  O18  1  0.245  0.755  0.523  1.0
[/CIF]
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The structure described by Ca4Mn4O11 crystallizes in the tetragonal P4/mmm space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a distorted q6 geometry to two equivalent O(2) and eight equivalent O(4) atoms. In the second Ca site, Ca(2) is bonded to two equivalent O(1), two equivalent O(3), and eight equivalent O(4) atoms to form CaO12 cuboctahedra that share corners with four equivalent Ca(2)O12 cuboctahedra, faces with four equivalent Ca(2)O12 cuboctahedra, faces with four equivalent Mn(2)O6 octahedra, and faces with four equivalent Mn(1)O5 square pyramids. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(1) and four equivalent O(4) atoms to form MnO5 square pyramids that share corners with four equivalent Mn(2)O6 octahedra,  a cornercorner with one Mn(1)O5 square pyramid, and faces with four equivalent Ca(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles are 10°. In the second Mn site, Mn(2) is bonded to one O(2), one O(3), and four equivalent O(4) atoms to form MnO6 octahedra that share corners with two equivalent Mn(2)O6 octahedra, corners with four equivalent Mn(1)O5 square pyramids, and faces with four equivalent Ca(2)O12 cuboctahedra. The corner-sharing octahedra are not tilted. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted linear geometry to four equivalent Ca(2) and two equivalent Mn(1) atoms. In the second O site, O(2) is bonded in a linear geometry to four equivalent Ca(1) and two equivalent Mn(2) atoms. In the third O site, O(3) is bonded to four equivalent Ca(2) and two equivalent Mn(2) atoms to form distorted corner-sharing OCa4Mn2 octahedra. The corner-sharing octahedra are not tilted. In the fourth O site, O(4) is bonded in a 6-coordinate geometry to two equivalent Ca(1), two equivalent Ca(2), one Mn(1), and one Mn(2) atom. is represented by the CIF file [CIF]
data_Ca4Mn4O11
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.432
_cell_length_b   5.432
_cell_length_c   7.634
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   225.249
_cell_formula_units_Z   1
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  0.500  0.000  0.750  1.0
  Ca  Ca1  1  0.500  0.000  0.250  1.0
  Ca  Ca2  1  0.000  0.500  0.750  1.0
  Ca  Ca3  1  0.000  0.500  0.250  1.0
  Mn  Mn4  1  0.000  0.000  0.006  1.0
  Mn  Mn5  1  0.000  0.000  0.494  1.0
  Mn  Mn6  1  0.500  0.500  0.993  1.0
  Mn  Mn7  1  0.500  0.500  0.507  1.0
  O  O8  1  0.000  0.000  0.250  1.0
  O  O9  1  0.500  0.500  0.750  1.0
  O  O10  1  0.500  0.500  0.250  1.0
  O  O11  1  0.755  0.755  0.977  1.0
  O  O12  1  0.755  0.755  0.523  1.0
  O  O13  1  0.245  0.245  0.977  1.0
  O  O14  1  0.245  0.245  0.523  1.0
  O  O15  1  0.755  0.245  0.977  1.0
  O  O16  1  0.755  0.245  0.523  1.0
  O  O17  1  0.245  0.755  0.977  1.0
  O  O18  1  0.245  0.755  0.523  1.0
[/CIF]
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