The structure described by CaEu4O5 is Caswellsilverite-like structured and crystallizes in the tetragonal I4/m space group. Ca(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form CaO6 octahedra that share corners with two equivalent Ca(1)O6 octahedra, corners with four equivalent Eu(1)O6 octahedra, and edges with twelve equivalent Eu(1)O6 octahedra. The corner-sharing octahedra are not tilted. Eu(1) is bonded to one O(1) and five equivalent O(2) atoms to form EuO6 octahedra that share  a cornercorner with one Ca(1)O6 octahedra, corners with five equivalent Eu(1)O6 octahedra, edges with three equivalent Ca(1)O6 octahedra, and edges with nine equivalent Eu(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-3°. There are two inequivalent O sites. In the first O site, O(2) is bonded to one Ca(1) and five equivalent Eu(1) atoms to form OCaEu5 octahedra that share  a cornercorner with one O(1)Ca2Eu4 octahedra, corners with five equivalent O(2)CaEu5 octahedra, edges with three equivalent O(1)Ca2Eu4 octahedra, and edges with nine equivalent O(2)CaEu5 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. In the second O site, O(1) is bonded to two equivalent Ca(1) and four equivalent Eu(1) atoms to form OCa2Eu4 octahedra that share corners with two equivalent O(1)Ca2Eu4 octahedra, corners with four equivalent O(2)CaEu5 octahedra, and edges with twelve equivalent O(2)CaEu5 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. is represented by the Crystallographic Information File (CIF) [CIF]
data_CaEu4O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.177
_cell_length_b   6.177
_cell_length_c   6.177
_cell_angle_alpha   99.613
_cell_angle_beta   99.613
_cell_angle_gamma   131.761
_symmetry_Int_Tables_number   1
_cell_volume   160.418
_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  0.000  0.000  0.000  1.0
  Eu  Eu1  1  0.799  0.600  0.399  1.0
  Eu  Eu2  1  0.400  0.799  0.200  1.0
  Eu  Eu3  1  0.600  0.201  0.800  1.0
  Eu  Eu4  1  0.201  0.400  0.601  1.0
  O  O5  1  0.500  0.500  0.000  1.0
  O  O6  1  0.293  0.098  0.391  1.0
  O  O7  1  0.902  0.293  0.194  1.0
  O  O8  1  0.098  0.707  0.806  1.0
  O  O9  1  0.707  0.902  0.609  1.0
[/CIF]
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The structure described by CaEu4O5 is Caswellsilverite-like structured and crystallizes in the tetragonal I4/m space group. Ca(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form CaO6 octahedra that share corners with two equivalent Ca(1)O6 octahedra, corners with four equivalent Eu(1)O6 octahedra, and edges with twelve equivalent Eu(1)O6 octahedra. The corner-sharing octahedra are not tilted. Eu(1) is bonded to one O(1) and five equivalent O(2) atoms to form EuO6 octahedra that share  a cornercorner with one Ca(1)O6 octahedra, corners with five equivalent Eu(1)O6 octahedra, edges with three equivalent Ca(1)O6 octahedra, and edges with nine equivalent Eu(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-3°. There are two inequivalent O sites. In the first O site, O(2) is bonded to one Ca(1) and five equivalent Eu(1) atoms to form OCaEu5 octahedra that share  a cornercorner with one O(1)Ca2Eu4 octahedra, corners with five equivalent O(2)CaEu5 octahedra, edges with three equivalent O(1)Ca2Eu4 octahedra, and edges with nine equivalent O(2)CaEu5 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. In the second O site, O(1) is bonded to two equivalent Ca(1) and four equivalent Eu(1) atoms to form OCa2Eu4 octahedra that share corners with two equivalent O(1)Ca2Eu4 octahedra, corners with four equivalent O(2)CaEu5 octahedra, and edges with twelve equivalent O(2)CaEu5 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. is represented by the Crystallographic Information File (CIF) [CIF]
data_CaEu4O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.177
_cell_length_b   6.177
_cell_length_c   6.177
_cell_angle_alpha   99.613
_cell_angle_beta   99.613
_cell_angle_gamma   131.761
_symmetry_Int_Tables_number   1
_cell_volume   160.418
_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  0.000  0.000  0.000  1.0
  Eu  Eu1  1  0.799  0.600  0.399  1.0
  Eu  Eu2  1  0.400  0.799  0.200  1.0
  Eu  Eu3  1  0.600  0.201  0.800  1.0
  Eu  Eu4  1  0.201  0.400  0.601  1.0
  O  O5  1  0.500  0.500  0.000  1.0
  O  O6  1  0.293  0.098  0.391  1.0
  O  O7  1  0.902  0.293  0.194  1.0
  O  O8  1  0.098  0.707  0.806  1.0
  O  O9  1  0.707  0.902  0.609  1.0
[/CIF]
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