The compound described by (Fe2As2)(Sr4MgTiO6) crystallizes in the tetragonal P4mm space group. There are four inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 4-coordinate geometry to four equivalent As(1) and four equivalent O(1) atoms. In the second Sr site, Sr(2) is bonded in a 8-coordinate geometry to four equivalent As(2) and four equivalent O(2) atoms. In the third Sr site, Sr(3) is bonded in a 9-coordinate geometry to one O(4), four equivalent O(1), and four equivalent O(3) atoms. In the fourth Sr site, Sr(4) is bonded in a 9-coordinate geometry to one O(3), four equivalent O(2), and four equivalent O(4) atoms. Mg(1) is bonded to one O(3) and four equivalent O(1) atoms to form corner-sharing MgO5 square pyramids. Ti(1) is bonded to one O(4) and four equivalent O(2) atoms to form corner-sharing TiO5 square pyramids. Fe(1) is bonded to two equivalent As(1) and two equivalent As(2) atoms to form a mixture of distorted corner and edge-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 Sr(1) and four equivalent Fe(1) atoms. In the second As site, As(2) is bonded in a 8-coordinate geometry to four equivalent Sr(2) and four equivalent Fe(1) atoms. There are four inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Sr(1), two equivalent Sr(3), and two equivalent Mg(1) atoms to form a mixture of distorted face, corner, and edge-sharing OSr4Mg2 octahedra. The corner-sharing octahedral tilt angles are 19°. In the second O site, O(2) is bonded in a 6-coordinate geometry to two equivalent Sr(2), two equivalent Sr(4), and two equivalent Ti(1) atoms. In the third O site, O(3) is bonded in a distorted linear geometry to one Sr(4), four equivalent Sr(3), and one Mg(1) atom. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to one Sr(3), four equivalent Sr(4), and one Ti(1) atom. is represented by the CIF card [CIF]
data_Sr4MgTiFe2(AsO3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.015
_cell_length_b   4.015
_cell_length_c   16.837
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   271.471
_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
  Sr  Sr0  1  0.000  0.000  0.791  1.0
  Sr  Sr1  1  0.500  0.500  0.195  1.0
  Sr  Sr2  1  0.000  0.000  0.599  1.0
  Sr  Sr3  1  0.500  0.500  0.426  1.0
  Mg  Mg4  1  0.500  0.500  0.683  1.0
  Ti  Ti5  1  0.000  0.000  0.311  1.0
  Fe  Fe6  1  0.000  0.500  0.004  1.0
  Fe  Fe7  1  0.500  0.000  0.004  1.0
  As  As8  1  0.500  0.500  0.909  1.0
  As  As9  1  0.000  0.000  0.105  1.0
  O  O10  1  0.000  0.500  0.704  1.0
  O  O11  1  0.500  0.000  0.704  1.0
  O  O12  1  0.500  0.000  0.293  1.0
  O  O13  1  0.000  0.500  0.293  1.0
  O  O14  1  0.500  0.500  0.560  1.0
  O  O15  1  0.000  0.000  0.418  1.0
[/CIF]
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The compound described by (Fe2As2)(Sr4MgTiO6) crystallizes in the tetragonal P4mm space group. There are four inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 4-coordinate geometry to four equivalent As(1) and four equivalent O(1) atoms. In the second Sr site, Sr(2) is bonded in a 8-coordinate geometry to four equivalent As(2) and four equivalent O(2) atoms. In the third Sr site, Sr(3) is bonded in a 9-coordinate geometry to one O(4), four equivalent O(1), and four equivalent O(3) atoms. In the fourth Sr site, Sr(4) is bonded in a 9-coordinate geometry to one O(3), four equivalent O(2), and four equivalent O(4) atoms. Mg(1) is bonded to one O(3) and four equivalent O(1) atoms to form corner-sharing MgO5 square pyramids. Ti(1) is bonded to one O(4) and four equivalent O(2) atoms to form corner-sharing TiO5 square pyramids. Fe(1) is bonded to two equivalent As(1) and two equivalent As(2) atoms to form a mixture of distorted corner and edge-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 Sr(1) and four equivalent Fe(1) atoms. In the second As site, As(2) is bonded in a 8-coordinate geometry to four equivalent Sr(2) and four equivalent Fe(1) atoms. There are four inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Sr(1), two equivalent Sr(3), and two equivalent Mg(1) atoms to form a mixture of distorted face, corner, and edge-sharing OSr4Mg2 octahedra. The corner-sharing octahedral tilt angles are 19°. In the second O site, O(2) is bonded in a 6-coordinate geometry to two equivalent Sr(2), two equivalent Sr(4), and two equivalent Ti(1) atoms. In the third O site, O(3) is bonded in a distorted linear geometry to one Sr(4), four equivalent Sr(3), and one Mg(1) atom. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to one Sr(3), four equivalent Sr(4), and one Ti(1) atom. is represented by the CIF card [CIF]
data_Sr4MgTiFe2(AsO3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.015
_cell_length_b   4.015
_cell_length_c   16.837
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   271.471
_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
  Sr  Sr0  1  0.000  0.000  0.791  1.0
  Sr  Sr1  1  0.500  0.500  0.195  1.0
  Sr  Sr2  1  0.000  0.000  0.599  1.0
  Sr  Sr3  1  0.500  0.500  0.426  1.0
  Mg  Mg4  1  0.500  0.500  0.683  1.0
  Ti  Ti5  1  0.000  0.000  0.311  1.0
  Fe  Fe6  1  0.000  0.500  0.004  1.0
  Fe  Fe7  1  0.500  0.000  0.004  1.0
  As  As8  1  0.500  0.500  0.909  1.0
  As  As9  1  0.000  0.000  0.105  1.0
  O  O10  1  0.000  0.500  0.704  1.0
  O  O11  1  0.500  0.000  0.704  1.0
  O  O12  1  0.500  0.000  0.293  1.0
  O  O13  1  0.000  0.500  0.293  1.0
  O  O14  1  0.500  0.500  0.560  1.0
  O  O15  1  0.000  0.000  0.418  1.0
[/CIF]
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