The material described by Sr3MgTi2O7 crystallizes in the orthorhombic Immm space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 3-coordinate geometry to one O(2) and two equivalent O(4) atoms. In the second Sr site, Sr(2) is bonded to two equivalent Mg(1) and four equivalent O(4) atoms to form distorted SrMg2O4 octahedra that share corners with two equivalent Sr(2)Mg2O4 octahedra, corners with eight equivalent Ti(1)O6 octahedra, and edges with two equivalent Sr(2)Mg2O4 octahedra. The corner-sharing octahedral tilt angles range from 0-86°. Mg(1) is bonded in a square co-planar geometry to two equivalent Sr(2), two equivalent O(1), and two equivalent O(3) atoms. Ti(1) is bonded to one O(2), one O(3), two equivalent O(1), and two equivalent O(4) atoms to form distorted TiO6 octahedra that share corners with four equivalent Sr(2)Mg2O4 octahedra and corners with five equivalent Ti(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-86°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to one Mg(1) and two equivalent Ti(1) atoms. In the second O site, O(2) is bonded in a distorted linear geometry to one Sr(1) and one Ti(1) atom. In the third O site, O(3) is bonded in a square co-planar geometry to two equivalent Mg(1) and two equivalent Ti(1) atoms. In the fourth O site, O(4) is bonded to two equivalent Sr(1), two equivalent Sr(2), and two equivalent Ti(1) atoms to form a mixture of corner and edge-sharing OSr4Ti2 octahedra. The corner-sharing octahedral tilt angles range from 0-13°. is represented by the CIF file [CIF]
data_Sr3MgTi2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.123
_cell_length_b   3.887
_cell_length_c   10.481
_cell_angle_alpha   100.686
_cell_angle_beta   104.147
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   198.662
_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  0.322  0.322  0.645  1.0
  Sr  Sr1  1  0.500  0.500  0.000  1.0
  Sr  Sr2  1  0.678  0.678  0.355  1.0
  Mg  Mg3  1  0.000  0.500  0.000  1.0
  Ti  Ti4  1  0.111  0.111  0.221  1.0
  Ti  Ti5  1  0.889  0.889  0.779  1.0
  O  O6  1  0.903  0.403  0.806  1.0
  O  O7  1  0.798  0.798  0.597  1.0
  O  O8  1  0.000  0.000  0.000  1.0
  O  O9  1  0.596  0.096  0.193  1.0
  O  O10  1  0.097  0.597  0.194  1.0
  O  O11  1  0.404  0.904  0.807  1.0
  O  O12  1  0.202  0.202  0.403  1.0
[/CIF]
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The material described by Sr3MgTi2O7 crystallizes in the orthorhombic Immm space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 3-coordinate geometry to one O(2) and two equivalent O(4) atoms. In the second Sr site, Sr(2) is bonded to two equivalent Mg(1) and four equivalent O(4) atoms to form distorted SrMg2O4 octahedra that share corners with two equivalent Sr(2)Mg2O4 octahedra, corners with eight equivalent Ti(1)O6 octahedra, and edges with two equivalent Sr(2)Mg2O4 octahedra. The corner-sharing octahedral tilt angles range from 0-86°. Mg(1) is bonded in a square co-planar geometry to two equivalent Sr(2), two equivalent O(1), and two equivalent O(3) atoms. Ti(1) is bonded to one O(2), one O(3), two equivalent O(1), and two equivalent O(4) atoms to form distorted TiO6 octahedra that share corners with four equivalent Sr(2)Mg2O4 octahedra and corners with five equivalent Ti(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-86°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to one Mg(1) and two equivalent Ti(1) atoms. In the second O site, O(2) is bonded in a distorted linear geometry to one Sr(1) and one Ti(1) atom. In the third O site, O(3) is bonded in a square co-planar geometry to two equivalent Mg(1) and two equivalent Ti(1) atoms. In the fourth O site, O(4) is bonded to two equivalent Sr(1), two equivalent Sr(2), and two equivalent Ti(1) atoms to form a mixture of corner and edge-sharing OSr4Ti2 octahedra. The corner-sharing octahedral tilt angles range from 0-13°. is represented by the CIF file [CIF]
data_Sr3MgTi2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.123
_cell_length_b   3.887
_cell_length_c   10.481
_cell_angle_alpha   100.686
_cell_angle_beta   104.147
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   198.662
_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  0.322  0.322  0.645  1.0
  Sr  Sr1  1  0.500  0.500  0.000  1.0
  Sr  Sr2  1  0.678  0.678  0.355  1.0
  Mg  Mg3  1  0.000  0.500  0.000  1.0
  Ti  Ti4  1  0.111  0.111  0.221  1.0
  Ti  Ti5  1  0.889  0.889  0.779  1.0
  O  O6  1  0.903  0.403  0.806  1.0
  O  O7  1  0.798  0.798  0.597  1.0
  O  O8  1  0.000  0.000  0.000  1.0
  O  O9  1  0.596  0.096  0.193  1.0
  O  O10  1  0.097  0.597  0.194  1.0
  O  O11  1  0.404  0.904  0.807  1.0
  O  O12  1  0.202  0.202  0.403  1.0
[/CIF]
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