The structure described by Sr3MgMn2O7 crystallizes in the orthorhombic Immm space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded to two equivalent Mg(1) and four equivalent O(1) atoms to form distorted SrMg2O4 octahedra that share corners with two equivalent Sr(1)Mg2O4 octahedra, corners with eight equivalent Mn(1)O6 octahedra, and edges with two equivalent Sr(1)Mg2O4 octahedra. The corner-sharing octahedral tilt angles range from 0-85°. In the second Sr site, Sr(2) is bonded in a 3-coordinate geometry to one O(3) and two equivalent O(1) atoms. Mg(1) is bonded in a square co-planar geometry to two equivalent Sr(1), two equivalent O(2), and two equivalent O(4) atoms. Mn(1) is bonded to one O(3), one O(4), two equivalent O(1), and two equivalent O(2) atoms to form distorted MnO6 octahedra that share corners with four equivalent Sr(1)Mg2O4 octahedra and corners with five equivalent Mn(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-85°. There are four inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Sr(1), two equivalent Sr(2), and two equivalent Mn(1) atoms to form a mixture of corner and edge-sharing OSr4Mn2 octahedra. The corner-sharing octahedral tilt angles range from 0-15°. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Mg(1) and two equivalent Mn(1) atoms. In the third O site, O(3) is bonded in a distorted linear geometry to one Sr(2) and one Mn(1) atom. In the fourth O site, O(4) is bonded in a square co-planar geometry to two equivalent Mg(1) and two equivalent Mn(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sr3MgMn2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.817
_cell_length_b   5.153
_cell_length_c   10.321
_cell_angle_alpha   104.455
_cell_angle_beta   100.656
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   192.960
_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  0.500  0.500  0.000  1.0
  Sr  Sr1  1  0.322  0.322  0.643  1.0
  Sr  Sr2  1  0.678  0.678  0.357  1.0
  Mg  Mg3  1  0.500  0.000  0.000  1.0
  Mn  Mn4  1  0.109  0.109  0.218  1.0
  Mn  Mn5  1  0.891  0.891  0.782  1.0
  O  O6  1  0.908  0.408  0.816  1.0
  O  O7  1  0.403  0.903  0.805  1.0
  O  O8  1  0.092  0.592  0.184  1.0
  O  O9  1  0.597  0.097  0.195  1.0
  O  O10  1  0.798  0.798  0.597  1.0
  O  O11  1  0.000  0.000  0.000  1.0
  O  O12  1  0.202  0.202  0.403  1.0
[/CIF]
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The structure described by Sr3MgMn2O7 crystallizes in the orthorhombic Immm space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded to two equivalent Mg(1) and four equivalent O(1) atoms to form distorted SrMg2O4 octahedra that share corners with two equivalent Sr(1)Mg2O4 octahedra, corners with eight equivalent Mn(1)O6 octahedra, and edges with two equivalent Sr(1)Mg2O4 octahedra. The corner-sharing octahedral tilt angles range from 0-85°. In the second Sr site, Sr(2) is bonded in a 3-coordinate geometry to one O(3) and two equivalent O(1) atoms. Mg(1) is bonded in a square co-planar geometry to two equivalent Sr(1), two equivalent O(2), and two equivalent O(4) atoms. Mn(1) is bonded to one O(3), one O(4), two equivalent O(1), and two equivalent O(2) atoms to form distorted MnO6 octahedra that share corners with four equivalent Sr(1)Mg2O4 octahedra and corners with five equivalent Mn(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-85°. There are four inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Sr(1), two equivalent Sr(2), and two equivalent Mn(1) atoms to form a mixture of corner and edge-sharing OSr4Mn2 octahedra. The corner-sharing octahedral tilt angles range from 0-15°. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Mg(1) and two equivalent Mn(1) atoms. In the third O site, O(3) is bonded in a distorted linear geometry to one Sr(2) and one Mn(1) atom. In the fourth O site, O(4) is bonded in a square co-planar geometry to two equivalent Mg(1) and two equivalent Mn(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sr3MgMn2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.817
_cell_length_b   5.153
_cell_length_c   10.321
_cell_angle_alpha   104.455
_cell_angle_beta   100.656
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   192.960
_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  0.500  0.500  0.000  1.0
  Sr  Sr1  1  0.322  0.322  0.643  1.0
  Sr  Sr2  1  0.678  0.678  0.357  1.0
  Mg  Mg3  1  0.500  0.000  0.000  1.0
  Mn  Mn4  1  0.109  0.109  0.218  1.0
  Mn  Mn5  1  0.891  0.891  0.782  1.0
  O  O6  1  0.908  0.408  0.816  1.0
  O  O7  1  0.403  0.903  0.805  1.0
  O  O8  1  0.092  0.592  0.184  1.0
  O  O9  1  0.597  0.097  0.195  1.0
  O  O10  1  0.798  0.798  0.597  1.0
  O  O11  1  0.000  0.000  0.000  1.0
  O  O12  1  0.202  0.202  0.403  1.0
[/CIF]
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