The material described by MgFeAsO5 crystallizes in the orthorhombic P2_12_12_1 space group. Mg(1) is bonded to one O(2), one O(3), one O(4), and one O(5) atom to form MgO4 tetrahedra that share corners with two equivalent Fe(1)O6 octahedra, corners with three equivalent As(1)O4 tetrahedra, and  an edgeedge with one Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 49-57°. 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 two equivalent Mg(1)O4 tetrahedra, corners with four equivalent As(1)O4 tetrahedra, edges with two equivalent Fe(1)O6 octahedra, and  an edgeedge with one Mg(1)O4 tetrahedra. 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 and corners with three equivalent Mg(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 39-62°. There are five inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to two equivalent Fe(1) and one As(1) atom. In the second O site, O(2) is bonded in a bent 120 degrees geometry to one Mg(1) and one As(1) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Mg(1), one Fe(1), and one As(1) atom. In the fourth O site, O(4) is bonded in a trigonal planar geometry to one Mg(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 Mg(1) and two equivalent Fe(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgFeAsO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.141
_cell_length_b   8.120
_cell_length_c   8.507
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   424.144
_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
  Mg  Mg0  1  0.109  0.844  0.682  1.0
  Mg  Mg1  1  0.391  0.156  0.182  1.0
  Mg  Mg2  1  0.891  0.344  0.818  1.0
  Mg  Mg3  1  0.609  0.656  0.318  1.0
  Fe  Fe4  1  0.259  0.752  0.005  1.0
  Fe  Fe5  1  0.241  0.248  0.505  1.0
  Fe  Fe6  1  0.741  0.252  0.495  1.0
  Fe  Fe7  1  0.759  0.748  0.995  1.0
  As  As8  1  0.479  0.093  0.821  1.0
  As  As9  1  0.021  0.907  0.321  1.0
  As  As10  1  0.521  0.593  0.679  1.0
  As  As11  1  0.979  0.407  0.179  1.0
  O  O12  1  0.515  0.904  0.915  1.0
  O  O13  1  0.985  0.096  0.415  1.0
  O  O14  1  0.485  0.404  0.585  1.0
  O  O15  1  0.015  0.596  0.085  1.0
  O  O16  1  0.412  0.230  0.963  1.0
  O  O17  1  0.088  0.770  0.463  1.0
  O  O18  1  0.588  0.730  0.537  1.0
  O  O19  1  0.912  0.270  0.037  1.0
  O  O20  1  0.715  0.152  0.727  1.0
  O  O21  1  0.785  0.848  0.227  1.0
  O  O22  1  0.285  0.652  0.773  1.0
  O  O23  1  0.215  0.348  0.273  1.0
  O  O24  1  0.272  0.067  0.686  1.0
  O  O25  1  0.228  0.933  0.186  1.0
  O  O26  1  0.728  0.567  0.814  1.0
  O  O27  1  0.772  0.433  0.314  1.0
  O  O28  1  0.003  0.851  0.899  1.0
  O  O29  1  0.497  0.149  0.399  1.0
  O  O30  1  0.997  0.351  0.601  1.0
  O  O31  1  0.503  0.649  0.101  1.0
[/CIF]
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The material described by MgFeAsO5 crystallizes in the orthorhombic P2_12_12_1 space group. Mg(1) is bonded to one O(2), one O(3), one O(4), and one O(5) atom to form MgO4 tetrahedra that share corners with two equivalent Fe(1)O6 octahedra, corners with three equivalent As(1)O4 tetrahedra, and  an edgeedge with one Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 49-57°. 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 two equivalent Mg(1)O4 tetrahedra, corners with four equivalent As(1)O4 tetrahedra, edges with two equivalent Fe(1)O6 octahedra, and  an edgeedge with one Mg(1)O4 tetrahedra. 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 and corners with three equivalent Mg(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 39-62°. There are five inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to two equivalent Fe(1) and one As(1) atom. In the second O site, O(2) is bonded in a bent 120 degrees geometry to one Mg(1) and one As(1) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Mg(1), one Fe(1), and one As(1) atom. In the fourth O site, O(4) is bonded in a trigonal planar geometry to one Mg(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 Mg(1) and two equivalent Fe(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgFeAsO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.141
_cell_length_b   8.120
_cell_length_c   8.507
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   424.144
_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
  Mg  Mg0  1  0.109  0.844  0.682  1.0
  Mg  Mg1  1  0.391  0.156  0.182  1.0
  Mg  Mg2  1  0.891  0.344  0.818  1.0
  Mg  Mg3  1  0.609  0.656  0.318  1.0
  Fe  Fe4  1  0.259  0.752  0.005  1.0
  Fe  Fe5  1  0.241  0.248  0.505  1.0
  Fe  Fe6  1  0.741  0.252  0.495  1.0
  Fe  Fe7  1  0.759  0.748  0.995  1.0
  As  As8  1  0.479  0.093  0.821  1.0
  As  As9  1  0.021  0.907  0.321  1.0
  As  As10  1  0.521  0.593  0.679  1.0
  As  As11  1  0.979  0.407  0.179  1.0
  O  O12  1  0.515  0.904  0.915  1.0
  O  O13  1  0.985  0.096  0.415  1.0
  O  O14  1  0.485  0.404  0.585  1.0
  O  O15  1  0.015  0.596  0.085  1.0
  O  O16  1  0.412  0.230  0.963  1.0
  O  O17  1  0.088  0.770  0.463  1.0
  O  O18  1  0.588  0.730  0.537  1.0
  O  O19  1  0.912  0.270  0.037  1.0
  O  O20  1  0.715  0.152  0.727  1.0
  O  O21  1  0.785  0.848  0.227  1.0
  O  O22  1  0.285  0.652  0.773  1.0
  O  O23  1  0.215  0.348  0.273  1.0
  O  O24  1  0.272  0.067  0.686  1.0
  O  O25  1  0.228  0.933  0.186  1.0
  O  O26  1  0.728  0.567  0.814  1.0
  O  O27  1  0.772  0.433  0.314  1.0
  O  O28  1  0.003  0.851  0.899  1.0
  O  O29  1  0.497  0.149  0.399  1.0
  O  O30  1  0.997  0.351  0.601  1.0
  O  O31  1  0.503  0.649  0.101  1.0
[/CIF]
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