The material structure described by Sr3MgFe2O7 crystallizes in the monoclinic C2/m space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded to one O(3), two equivalent O(1), and three equivalent O(2) atoms to form distorted edge-sharing SrO6 pentagonal pyramids. In the second Sr site, Sr(2) is bonded in a distorted square co-planar geometry to four equivalent O(1) atoms. Mg(1) is bonded in a square co-planar geometry to two equivalent O(3) and two equivalent O(4) atoms. Fe(1) is bonded in a 5-coordinate geometry to one O(1), one O(2), one O(4), and two equivalent O(3) atoms. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to two equivalent Sr(1), two equivalent Sr(2), and one Fe(1) atom. In the second O site, O(2) is bonded to three equivalent Sr(1) and one Fe(1) atom to form a mixture of distorted edge and corner-sharing OSr3Fe trigonal pyramids. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Sr(1), one Mg(1), and two equivalent Fe(1) atoms. In the fourth O site, O(4) is bonded in a square co-planar geometry to two equivalent Mg(1) and two equivalent Fe(1) atoms. is represented by the CIF file [CIF]
data_Sr3MgFe2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.507
_cell_length_b   3.773
_cell_length_c   10.413
_cell_angle_alpha   100.442
_cell_angle_beta   103.555
_cell_angle_gamma   89.997
_symmetry_Int_Tables_number   1
_cell_volume   206.610
_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  0.795  0.680  0.360  1.0
  Sr  Sr1  1  0.205  0.320  0.640  1.0
  Sr  Sr2  1  0.500  0.500  0.000  1.0
  Mg  Mg3  1  0.000  0.500  0.000  1.0
  Fe  Fe4  1  0.822  0.888  0.776  1.0
  Fe  Fe5  1  0.178  0.112  0.224  1.0
  O  O6  1  0.491  0.905  0.811  1.0
  O  O7  1  0.509  0.095  0.189  1.0
  O  O8  1  0.886  0.801  0.602  1.0
  O  O9  1  0.954  0.405  0.809  1.0
  O  O10  1  0.000  0.000  0.000  1.0
  O  O11  1  0.046  0.595  0.191  1.0
  O  O12  1  0.114  0.199  0.398  1.0
[/CIF]
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The material structure described by Sr3MgFe2O7 crystallizes in the monoclinic C2/m space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded to one O(3), two equivalent O(1), and three equivalent O(2) atoms to form distorted edge-sharing SrO6 pentagonal pyramids. In the second Sr site, Sr(2) is bonded in a distorted square co-planar geometry to four equivalent O(1) atoms. Mg(1) is bonded in a square co-planar geometry to two equivalent O(3) and two equivalent O(4) atoms. Fe(1) is bonded in a 5-coordinate geometry to one O(1), one O(2), one O(4), and two equivalent O(3) atoms. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to two equivalent Sr(1), two equivalent Sr(2), and one Fe(1) atom. In the second O site, O(2) is bonded to three equivalent Sr(1) and one Fe(1) atom to form a mixture of distorted edge and corner-sharing OSr3Fe trigonal pyramids. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Sr(1), one Mg(1), and two equivalent Fe(1) atoms. In the fourth O site, O(4) is bonded in a square co-planar geometry to two equivalent Mg(1) and two equivalent Fe(1) atoms. is represented by the CIF file [CIF]
data_Sr3MgFe2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.507
_cell_length_b   3.773
_cell_length_c   10.413
_cell_angle_alpha   100.442
_cell_angle_beta   103.555
_cell_angle_gamma   89.997
_symmetry_Int_Tables_number   1
_cell_volume   206.610
_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  0.795  0.680  0.360  1.0
  Sr  Sr1  1  0.205  0.320  0.640  1.0
  Sr  Sr2  1  0.500  0.500  0.000  1.0
  Mg  Mg3  1  0.000  0.500  0.000  1.0
  Fe  Fe4  1  0.822  0.888  0.776  1.0
  Fe  Fe5  1  0.178  0.112  0.224  1.0
  O  O6  1  0.491  0.905  0.811  1.0
  O  O7  1  0.509  0.095  0.189  1.0
  O  O8  1  0.886  0.801  0.602  1.0
  O  O9  1  0.954  0.405  0.809  1.0
  O  O10  1  0.000  0.000  0.000  1.0
  O  O11  1  0.046  0.595  0.191  1.0
  O  O12  1  0.114  0.199  0.398  1.0
[/CIF]
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