The material described by BaEu2Mn2O7 crystallizes in the tetragonal I4/mmm space group. Ba(1) is bonded to four equivalent O(1) and eight equivalent O(3) atoms to form BaO12 cuboctahedra that share corners with four equivalent Ba(1)O12 cuboctahedra, faces with four equivalent Ba(1)O12 cuboctahedra, and faces with eight equivalent Mn(1)O6 octahedra. Eu(1) is bonded in a 9-coordinate geometry to four equivalent O(3) and five equivalent O(2) atoms. Mn(1) is bonded to one O(1), one O(2), and four equivalent O(3) atoms to form MnO6 octahedra that share corners with five equivalent Mn(1)O6 octahedra and faces with four equivalent Ba(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-6°. There are three inequivalent O sites. In the first O site, O(1) is bonded to four equivalent Ba(1) and two equivalent Mn(1) atoms to form distorted OBa4Mn2 octahedra that share corners with two equivalent O(2)Eu5Mn octahedra, corners with four equivalent O(1)Ba4Mn2 octahedra, corners with sixteen equivalent O(3)Ba2Eu2Mn2 octahedra, edges with four equivalent O(1)Ba4Mn2 octahedra, and faces with eight equivalent O(3)Ba2Eu2Mn2 octahedra. The corner-sharing octahedral tilt angles range from 0-61°. In the second O site, O(2) is bonded to five equivalent Eu(1) and one Mn(1) atom to form distorted OEu5Mn octahedra that share  a cornercorner with one O(1)Ba4Mn2 octahedra, corners with four equivalent O(2)Eu5Mn octahedra, corners with twelve equivalent O(3)Ba2Eu2Mn2 octahedra, edges with eight equivalent O(2)Eu5Mn octahedra, and faces with four equivalent O(3)Ba2Eu2Mn2 octahedra. The corner-sharing octahedral tilt angles range from 0-52°. In the third O site, O(3) is bonded to two equivalent Ba(1), two equivalent Eu(1), and two equivalent Mn(1) atoms to form distorted OBa2Eu2Mn2 octahedra that share corners with four equivalent O(1)Ba4Mn2 octahedra, corners with six equivalent O(2)Eu5Mn octahedra, corners with eight equivalent O(3)Ba2Eu2Mn2 octahedra, edges with three equivalent O(3)Ba2Eu2Mn2 octahedra, faces with two equivalent O(1)Ba4Mn2 octahedra, faces with two equivalent O(2)Eu5Mn octahedra, and faces with four equivalent O(3)Ba2Eu2Mn2 octahedra. The corner-sharing octahedral tilt angles range from 0-61°. is represented by the CIF file [CIF]
data_BaEu2Mn2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.340
_cell_length_b   10.340
_cell_length_c   10.340
_cell_angle_alpha   158.286
_cell_angle_beta   158.286
_cell_angle_gamma   30.898
_symmetry_Int_Tables_number   1
_cell_volume   151.211
_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
  Ba  Ba0  1  0.500  0.500  0.000  1.0
  Eu  Eu1  1  0.684  0.684  0.000  1.0
  Eu  Eu2  1  0.316  0.316  0.000  1.0
  Mn  Mn3  1  0.900  0.900  0.000  1.0
  Mn  Mn4  1  0.100  0.100  0.000  1.0
  O  O5  1  0.000  0.000  0.000  1.0
  O  O6  1  0.199  0.199  0.000  1.0
  O  O7  1  0.801  0.801  0.000  1.0
  O  O8  1  0.395  0.895  0.500  1.0
  O  O9  1  0.105  0.605  0.500  1.0
  O  O10  1  0.605  0.105  0.500  1.0
  O  O11  1  0.895  0.395  0.500  1.0
[/CIF]
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The material described by BaEu2Mn2O7 crystallizes in the tetragonal I4/mmm space group. Ba(1) is bonded to four equivalent O(1) and eight equivalent O(3) atoms to form BaO12 cuboctahedra that share corners with four equivalent Ba(1)O12 cuboctahedra, faces with four equivalent Ba(1)O12 cuboctahedra, and faces with eight equivalent Mn(1)O6 octahedra. Eu(1) is bonded in a 9-coordinate geometry to four equivalent O(3) and five equivalent O(2) atoms. Mn(1) is bonded to one O(1), one O(2), and four equivalent O(3) atoms to form MnO6 octahedra that share corners with five equivalent Mn(1)O6 octahedra and faces with four equivalent Ba(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-6°. There are three inequivalent O sites. In the first O site, O(1) is bonded to four equivalent Ba(1) and two equivalent Mn(1) atoms to form distorted OBa4Mn2 octahedra that share corners with two equivalent O(2)Eu5Mn octahedra, corners with four equivalent O(1)Ba4Mn2 octahedra, corners with sixteen equivalent O(3)Ba2Eu2Mn2 octahedra, edges with four equivalent O(1)Ba4Mn2 octahedra, and faces with eight equivalent O(3)Ba2Eu2Mn2 octahedra. The corner-sharing octahedral tilt angles range from 0-61°. In the second O site, O(2) is bonded to five equivalent Eu(1) and one Mn(1) atom to form distorted OEu5Mn octahedra that share  a cornercorner with one O(1)Ba4Mn2 octahedra, corners with four equivalent O(2)Eu5Mn octahedra, corners with twelve equivalent O(3)Ba2Eu2Mn2 octahedra, edges with eight equivalent O(2)Eu5Mn octahedra, and faces with four equivalent O(3)Ba2Eu2Mn2 octahedra. The corner-sharing octahedral tilt angles range from 0-52°. In the third O site, O(3) is bonded to two equivalent Ba(1), two equivalent Eu(1), and two equivalent Mn(1) atoms to form distorted OBa2Eu2Mn2 octahedra that share corners with four equivalent O(1)Ba4Mn2 octahedra, corners with six equivalent O(2)Eu5Mn octahedra, corners with eight equivalent O(3)Ba2Eu2Mn2 octahedra, edges with three equivalent O(3)Ba2Eu2Mn2 octahedra, faces with two equivalent O(1)Ba4Mn2 octahedra, faces with two equivalent O(2)Eu5Mn octahedra, and faces with four equivalent O(3)Ba2Eu2Mn2 octahedra. The corner-sharing octahedral tilt angles range from 0-61°. is represented by the CIF file [CIF]
data_BaEu2Mn2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.340
_cell_length_b   10.340
_cell_length_c   10.340
_cell_angle_alpha   158.286
_cell_angle_beta   158.286
_cell_angle_gamma   30.898
_symmetry_Int_Tables_number   1
_cell_volume   151.211
_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
  Ba  Ba0  1  0.500  0.500  0.000  1.0
  Eu  Eu1  1  0.684  0.684  0.000  1.0
  Eu  Eu2  1  0.316  0.316  0.000  1.0
  Mn  Mn3  1  0.900  0.900  0.000  1.0
  Mn  Mn4  1  0.100  0.100  0.000  1.0
  O  O5  1  0.000  0.000  0.000  1.0
  O  O6  1  0.199  0.199  0.000  1.0
  O  O7  1  0.801  0.801  0.000  1.0
  O  O8  1  0.395  0.895  0.500  1.0
  O  O9  1  0.105  0.605  0.500  1.0
  O  O10  1  0.605  0.105  0.500  1.0
  O  O11  1  0.895  0.395  0.500  1.0
[/CIF]
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