The compound described by CaFeAsO5 is Esseneite-like structured and crystallizes in the orthorhombic P2_12_12_1 space group. Ca(1) is bonded in a 8-coordinate geometry to one O(1), one O(5), two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms. Fe(1) is bonded to one O(3), one O(4), two equivalent O(1), and two equivalent O(5) atoms to form FeO6 octahedra that share corners with four equivalent As(1)O4 tetrahedra and edges with two equivalent Fe(1)O6 octahedra. As(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form AsO4 tetrahedra that share corners with four equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 39-60°. There are five inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Ca(1), two equivalent Fe(1), and one As(1) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to two equivalent Ca(1) and one As(1) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to two equivalent Ca(1), one Fe(1), and one As(1) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to two equivalent Ca(1), one Fe(1), and one As(1) atom. In the fifth O site, O(5) is bonded in a trigonal non-coplanar geometry to one Ca(1) and two equivalent Fe(1) atoms. is represented by the CIF file [CIF]
data_CaFeAsO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.989
_cell_length_b   7.709
_cell_length_c   9.044
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   417.592
_cell_formula_units_Z   4
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  0.975  0.853  0.670  1.0
  Ca  Ca1  1  0.525  0.147  0.170  1.0
  Ca  Ca2  1  0.025  0.353  0.830  1.0
  Ca  Ca3  1  0.475  0.647  0.330  1.0
  Fe  Fe4  1  0.254  0.758  0.995  1.0
  Fe  Fe5  1  0.246  0.242  0.495  1.0
  Fe  Fe6  1  0.746  0.258  0.505  1.0
  Fe  Fe7  1  0.754  0.742  0.005  1.0
  As  As8  1  0.481  0.111  0.815  1.0
  As  As9  1  0.019  0.889  0.315  1.0
  As  As10  1  0.519  0.611  0.685  1.0
  As  As11  1  0.981  0.389  0.185  1.0
  O  O12  1  0.508  0.929  0.931  1.0
  O  O13  1  0.992  0.071  0.431  1.0
  O  O14  1  0.492  0.429  0.569  1.0
  O  O15  1  0.008  0.571  0.069  1.0
  O  O16  1  0.414  0.274  0.934  1.0
  O  O17  1  0.086  0.726  0.434  1.0
  O  O18  1  0.586  0.774  0.566  1.0
  O  O19  1  0.914  0.226  0.066  1.0
  O  O20  1  0.732  0.138  0.722  1.0
  O  O21  1  0.768  0.862  0.222  1.0
  O  O22  1  0.268  0.638  0.778  1.0
  O  O23  1  0.232  0.362  0.278  1.0
  O  O24  1  0.254  0.095  0.697  1.0
  O  O25  1  0.246  0.905  0.197  1.0
  O  O26  1  0.746  0.595  0.803  1.0
  O  O27  1  0.754  0.405  0.303  1.0
  O  O28  1  0.995  0.869  0.920  1.0
  O  O29  1  0.505  0.131  0.420  1.0
  O  O30  1  0.005  0.369  0.580  1.0
  O  O31  1  0.495  0.631  0.080  1.0
[/CIF]
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The compound described by CaFeAsO5 is Esseneite-like structured and crystallizes in the orthorhombic P2_12_12_1 space group. Ca(1) is bonded in a 8-coordinate geometry to one O(1), one O(5), two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms. Fe(1) is bonded to one O(3), one O(4), two equivalent O(1), and two equivalent O(5) atoms to form FeO6 octahedra that share corners with four equivalent As(1)O4 tetrahedra and edges with two equivalent Fe(1)O6 octahedra. As(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form AsO4 tetrahedra that share corners with four equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 39-60°. There are five inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Ca(1), two equivalent Fe(1), and one As(1) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to two equivalent Ca(1) and one As(1) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to two equivalent Ca(1), one Fe(1), and one As(1) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to two equivalent Ca(1), one Fe(1), and one As(1) atom. In the fifth O site, O(5) is bonded in a trigonal non-coplanar geometry to one Ca(1) and two equivalent Fe(1) atoms. is represented by the CIF file [CIF]
data_CaFeAsO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.989
_cell_length_b   7.709
_cell_length_c   9.044
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   417.592
_cell_formula_units_Z   4
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  0.975  0.853  0.670  1.0
  Ca  Ca1  1  0.525  0.147  0.170  1.0
  Ca  Ca2  1  0.025  0.353  0.830  1.0
  Ca  Ca3  1  0.475  0.647  0.330  1.0
  Fe  Fe4  1  0.254  0.758  0.995  1.0
  Fe  Fe5  1  0.246  0.242  0.495  1.0
  Fe  Fe6  1  0.746  0.258  0.505  1.0
  Fe  Fe7  1  0.754  0.742  0.005  1.0
  As  As8  1  0.481  0.111  0.815  1.0
  As  As9  1  0.019  0.889  0.315  1.0
  As  As10  1  0.519  0.611  0.685  1.0
  As  As11  1  0.981  0.389  0.185  1.0
  O  O12  1  0.508  0.929  0.931  1.0
  O  O13  1  0.992  0.071  0.431  1.0
  O  O14  1  0.492  0.429  0.569  1.0
  O  O15  1  0.008  0.571  0.069  1.0
  O  O16  1  0.414  0.274  0.934  1.0
  O  O17  1  0.086  0.726  0.434  1.0
  O  O18  1  0.586  0.774  0.566  1.0
  O  O19  1  0.914  0.226  0.066  1.0
  O  O20  1  0.732  0.138  0.722  1.0
  O  O21  1  0.768  0.862  0.222  1.0
  O  O22  1  0.268  0.638  0.778  1.0
  O  O23  1  0.232  0.362  0.278  1.0
  O  O24  1  0.254  0.095  0.697  1.0
  O  O25  1  0.246  0.905  0.197  1.0
  O  O26  1  0.746  0.595  0.803  1.0
  O  O27  1  0.754  0.405  0.303  1.0
  O  O28  1  0.995  0.869  0.920  1.0
  O  O29  1  0.505  0.131  0.420  1.0
  O  O30  1  0.005  0.369  0.580  1.0
  O  O31  1  0.495  0.631  0.080  1.0
[/CIF]
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