The material described by CeFeAsO is Parent of FeAs superconductors structured and crystallizes in the tetragonal P4mm space group. There are two inequivalent Ce sites. In the first Ce site, Ce(1) is bonded in a 4-coordinate geometry to four equivalent As(2) and four equivalent O(1) atoms. In the second Ce site, Ce(2) is bonded in a 4-coordinate geometry to four equivalent As(1) and four equivalent O(1) atoms. Fe(1) is bonded to two equivalent As(1) and two equivalent As(2) atoms to form a mixture of distorted edge and corner-sharing FeAs4 tetrahedra. There are two inequivalent As sites. In the first As site, As(1) is bonded in a 8-coordinate geometry to four equivalent Ce(2) and four equivalent Fe(1) atoms. In the second As site, As(2) is bonded in a 8-coordinate geometry to four equivalent Ce(1) and four equivalent Fe(1) atoms. O(1) is bonded to two equivalent Ce(1) and two equivalent Ce(2) atoms to form a mixture of edge and corner-sharing OCe4 tetrahedra. is represented by the CIF card [CIF]
data_CeFeAsO
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.992
_cell_length_b   3.992
_cell_length_c   9.042
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   144.112
_cell_formula_units_Z   2
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
  Ce  Ce0  1  0.500  0.500  0.858  1.0
  Ce  Ce1  1  0.000  0.000  0.132  1.0
  Fe  Fe2  1  0.000  0.500  0.502  1.0
  Fe  Fe3  1  0.500  0.000  0.502  1.0
  As  As4  1  0.500  0.500  0.315  1.0
  As  As5  1  0.000  0.000  0.689  1.0
  O  O6  1  0.000  0.500  0.997  1.0
  O  O7  1  0.500  0.000  0.997  1.0
[/CIF]
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The material described by CeFeAsO is Parent of FeAs superconductors structured and crystallizes in the tetragonal P4mm space group. There are two inequivalent Ce sites. In the first Ce site, Ce(1) is bonded in a 4-coordinate geometry to four equivalent As(2) and four equivalent O(1) atoms. In the second Ce site, Ce(2) is bonded in a 4-coordinate geometry to four equivalent As(1) and four equivalent O(1) atoms. Fe(1) is bonded to two equivalent As(1) and two equivalent As(2) atoms to form a mixture of distorted edge and corner-sharing FeAs4 tetrahedra. There are two inequivalent As sites. In the first As site, As(1) is bonded in a 8-coordinate geometry to four equivalent Ce(2) and four equivalent Fe(1) atoms. In the second As site, As(2) is bonded in a 8-coordinate geometry to four equivalent Ce(1) and four equivalent Fe(1) atoms. O(1) is bonded to two equivalent Ce(1) and two equivalent Ce(2) atoms to form a mixture of edge and corner-sharing OCe4 tetrahedra. is represented by the CIF card [CIF]
data_CeFeAsO
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.992
_cell_length_b   3.992
_cell_length_c   9.042
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   144.112
_cell_formula_units_Z   2
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
  Ce  Ce0  1  0.500  0.500  0.858  1.0
  Ce  Ce1  1  0.000  0.000  0.132  1.0
  Fe  Fe2  1  0.000  0.500  0.502  1.0
  Fe  Fe3  1  0.500  0.000  0.502  1.0
  As  As4  1  0.500  0.500  0.315  1.0
  As  As5  1  0.000  0.000  0.689  1.0
  O  O6  1  0.000  0.500  0.997  1.0
  O  O7  1  0.500  0.000  0.997  1.0
[/CIF]
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