The compound described by Sr2Ti2O5 crystallizes in the orthorhombic Cmmm space group. Sr(1) is bonded in a distorted q6 geometry to two equivalent O(3), four equivalent O(1), and four equivalent O(2) atoms. Ti(1) is bonded to one O(3), two equivalent O(1), and two equivalent O(2) atoms to form corner-sharing TiO5 square pyramids. There are three inequivalent O sites. In the first O site, O(1) is bonded to four equivalent Sr(1) and two equivalent Ti(1) atoms to form a mixture of distorted corner and edge-sharing OSr4Ti2 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. In the second O site, O(2) is bonded in a 6-coordinate geometry to four equivalent Sr(1) and two equivalent Ti(1) atoms. In the third O site, O(3) is bonded in a distorted linear geometry to four equivalent Sr(1) and two equivalent Ti(1) atoms. is represented by the CIF file [CIF]
data_Sr2Ti2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.574
_cell_length_b   5.574
_cell_length_c   3.940
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.983
_symmetry_Int_Tables_number   1
_cell_volume   122.413
_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  0.754  0.246  0.000  1.0
  Sr  Sr1  1  0.246  0.754  0.000  1.0
  Ti  Ti2  1  0.750  0.750  0.500  1.0
  Ti  Ti3  1  0.250  0.250  0.500  1.0
  O  O4  1  0.000  0.500  0.500  1.0
  O  O5  1  0.500  0.000  0.500  1.0
  O  O6  1  0.725  0.725  0.000  1.0
  O  O7  1  0.275  0.275  0.000  1.0
  O  O8  1  0.000  0.000  0.500  1.0
[/CIF]
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The compound described by Sr2Ti2O5 crystallizes in the orthorhombic Cmmm space group. Sr(1) is bonded in a distorted q6 geometry to two equivalent O(3), four equivalent O(1), and four equivalent O(2) atoms. Ti(1) is bonded to one O(3), two equivalent O(1), and two equivalent O(2) atoms to form corner-sharing TiO5 square pyramids. There are three inequivalent O sites. In the first O site, O(1) is bonded to four equivalent Sr(1) and two equivalent Ti(1) atoms to form a mixture of distorted corner and edge-sharing OSr4Ti2 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. In the second O site, O(2) is bonded in a 6-coordinate geometry to four equivalent Sr(1) and two equivalent Ti(1) atoms. In the third O site, O(3) is bonded in a distorted linear geometry to four equivalent Sr(1) and two equivalent Ti(1) atoms. is represented by the CIF file [CIF]
data_Sr2Ti2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.574
_cell_length_b   5.574
_cell_length_c   3.940
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.983
_symmetry_Int_Tables_number   1
_cell_volume   122.413
_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  0.754  0.246  0.000  1.0
  Sr  Sr1  1  0.246  0.754  0.000  1.0
  Ti  Ti2  1  0.750  0.750  0.500  1.0
  Ti  Ti3  1  0.250  0.250  0.500  1.0
  O  O4  1  0.000  0.500  0.500  1.0
  O  O5  1  0.500  0.000  0.500  1.0
  O  O6  1  0.725  0.725  0.000  1.0
  O  O7  1  0.275  0.275  0.000  1.0
  O  O8  1  0.000  0.000  0.500  1.0
[/CIF]
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