The structure described by Eu2As2O5 crystallizes in the tetragonal P4/mmm space group. There are two inequivalent Eu sites. In the first Eu site, Eu(1) is bonded in a body-centered cubic geometry to eight equivalent O(1) atoms. In the second Eu site, Eu(2) is bonded to four equivalent O(2) and eight equivalent O(1) atoms to form EuO12 cuboctahedra that share corners with four equivalent Eu(2)O12 cuboctahedra, faces with four equivalent Eu(2)O12 cuboctahedra, and faces with eight equivalent As(1)O5 square pyramids. As(1) is bonded to one O(2) and four equivalent O(1) atoms to form AsO5 square pyramids that share corners with five equivalent As(1)O5 square pyramids and faces with four equivalent Eu(2)O12 cuboctahedra. There are two inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Eu(1), two equivalent Eu(2), and two equivalent As(1) atoms to form a mixture of distorted face, corner, and edge-sharing OEu4As2 octahedra. The corner-sharing octahedral tilt angles range from 0-67°. In the second O site, O(2) is bonded in a distorted linear geometry to four equivalent Eu(2) and two equivalent As(1) atoms. is represented by the CIF card [CIF]
data_Eu2As2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.182
_cell_length_b   4.182
_cell_length_c   7.264
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   127.029
_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
  Eu  Eu0  1  0.000  0.000  0.000  1.0
  Eu  Eu1  1  0.000  0.000  0.500  1.0
  As  As2  1  0.500  0.500  0.234  1.0
  As  As3  1  0.500  0.500  0.766  1.0
  O  O4  1  0.500  0.000  0.233  1.0
  O  O5  1  0.500  0.000  0.767  1.0
  O  O6  1  0.500  0.500  0.500  1.0
  O  O7  1  0.000  0.500  0.233  1.0
  O  O8  1  0.000  0.500  0.767  1.0
[/CIF]
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The structure described by Eu2As2O5 crystallizes in the tetragonal P4/mmm space group. There are two inequivalent Eu sites. In the first Eu site, Eu(1) is bonded in a body-centered cubic geometry to eight equivalent O(1) atoms. In the second Eu site, Eu(2) is bonded to four equivalent O(2) and eight equivalent O(1) atoms to form EuO12 cuboctahedra that share corners with four equivalent Eu(2)O12 cuboctahedra, faces with four equivalent Eu(2)O12 cuboctahedra, and faces with eight equivalent As(1)O5 square pyramids. As(1) is bonded to one O(2) and four equivalent O(1) atoms to form AsO5 square pyramids that share corners with five equivalent As(1)O5 square pyramids and faces with four equivalent Eu(2)O12 cuboctahedra. There are two inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Eu(1), two equivalent Eu(2), and two equivalent As(1) atoms to form a mixture of distorted face, corner, and edge-sharing OEu4As2 octahedra. The corner-sharing octahedral tilt angles range from 0-67°. In the second O site, O(2) is bonded in a distorted linear geometry to four equivalent Eu(2) and two equivalent As(1) atoms. is represented by the CIF card [CIF]
data_Eu2As2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.182
_cell_length_b   4.182
_cell_length_c   7.264
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   127.029
_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
  Eu  Eu0  1  0.000  0.000  0.000  1.0
  Eu  Eu1  1  0.000  0.000  0.500  1.0
  As  As2  1  0.500  0.500  0.234  1.0
  As  As3  1  0.500  0.500  0.766  1.0
  O  O4  1  0.500  0.000  0.233  1.0
  O  O5  1  0.500  0.000  0.767  1.0
  O  O6  1  0.500  0.500  0.500  1.0
  O  O7  1  0.000  0.500  0.233  1.0
  O  O8  1  0.000  0.500  0.767  1.0
[/CIF]
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