The compound described by Ba2Ti2O5 crystallizes in the orthorhombic Imma space group. Ba(1) is bonded in a 10-coordinate geometry to two equivalent O(3), four equivalent O(1), and four equivalent O(2) atoms. There are two inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form TiO6 octahedra that share corners with four equivalent Ti(1)O6 octahedra and corners with two equivalent Ti(2)O4 trigonal pyramids. The corner-sharing octahedral tilt angles are 3°. In the second Ti site, Ti(2) is bonded to two equivalent O(2) and two equivalent O(3) atoms to form distorted TiO4 trigonal pyramids that share corners with two equivalent Ti(1)O6 octahedra and corners with two equivalent Ti(2)O4 trigonal pyramids. The corner-sharing octahedral tilt angles are 13°. There are three inequivalent O sites. In the first O site, O(1) is bonded to four equivalent Ba(1) and two equivalent Ti(1) atoms to form a mixture of distorted edge, face, and corner-sharing OBa4Ti2 octahedra. The corner-sharing octahedra are not tilted. In the second O site, O(2) is bonded in a 6-coordinate geometry to four equivalent Ba(1), one Ti(1), and one Ti(2) atom. In the third O site, O(3) is bonded in a distorted linear geometry to four equivalent Ba(1) and two equivalent Ti(2) atoms. is represented by the CIF file [CIF]
data_Ba2Ti2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.022
_cell_length_b   9.022
_cell_length_c   9.022
_cell_angle_alpha   142.288
_cell_angle_beta   142.284
_cell_angle_gamma   54.399
_symmetry_Int_Tables_number   1
_cell_volume   272.885
_cell_formula_units_Z   2
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
  Ba  Ba0  1  0.116  0.118  0.998  1.0
  Ba  Ba1  1  0.884  0.882  0.002  1.0
  Ba  Ba2  1  0.621  0.618  0.002  1.0
  Ba  Ba3  1  0.379  0.382  0.998  1.0
  Ti  Ti4  1  0.000  0.500  0.500  1.0
  Ti  Ti5  1  0.500  0.000  0.500  1.0
  Ti  Ti6  1  0.288  0.750  0.538  1.0
  Ti  Ti7  1  0.712  0.250  0.462  1.0
  O  O8  1  0.747  0.747  0.500  1.0
  O  O9  1  0.253  0.753  0.000  1.0
  O  O10  1  0.747  0.247  0.000  1.0
  O  O11  1  0.253  0.253  0.500  1.0
  O  O12  1  0.111  0.630  0.480  1.0
  O  O13  1  0.889  0.370  0.520  1.0
  O  O14  1  0.650  0.130  0.520  1.0
  O  O15  1  0.350  0.870  0.480  1.0
  O  O16  1  0.500  0.500  0.500  1.0
  O  O17  1  0.500  0.000  0.000  1.0
[/CIF]
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The compound described by Ba2Ti2O5 crystallizes in the orthorhombic Imma space group. Ba(1) is bonded in a 10-coordinate geometry to two equivalent O(3), four equivalent O(1), and four equivalent O(2) atoms. There are two inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form TiO6 octahedra that share corners with four equivalent Ti(1)O6 octahedra and corners with two equivalent Ti(2)O4 trigonal pyramids. The corner-sharing octahedral tilt angles are 3°. In the second Ti site, Ti(2) is bonded to two equivalent O(2) and two equivalent O(3) atoms to form distorted TiO4 trigonal pyramids that share corners with two equivalent Ti(1)O6 octahedra and corners with two equivalent Ti(2)O4 trigonal pyramids. The corner-sharing octahedral tilt angles are 13°. There are three inequivalent O sites. In the first O site, O(1) is bonded to four equivalent Ba(1) and two equivalent Ti(1) atoms to form a mixture of distorted edge, face, and corner-sharing OBa4Ti2 octahedra. The corner-sharing octahedra are not tilted. In the second O site, O(2) is bonded in a 6-coordinate geometry to four equivalent Ba(1), one Ti(1), and one Ti(2) atom. In the third O site, O(3) is bonded in a distorted linear geometry to four equivalent Ba(1) and two equivalent Ti(2) atoms. is represented by the CIF file [CIF]
data_Ba2Ti2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.022
_cell_length_b   9.022
_cell_length_c   9.022
_cell_angle_alpha   142.288
_cell_angle_beta   142.284
_cell_angle_gamma   54.399
_symmetry_Int_Tables_number   1
_cell_volume   272.885
_cell_formula_units_Z   2
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
  Ba  Ba0  1  0.116  0.118  0.998  1.0
  Ba  Ba1  1  0.884  0.882  0.002  1.0
  Ba  Ba2  1  0.621  0.618  0.002  1.0
  Ba  Ba3  1  0.379  0.382  0.998  1.0
  Ti  Ti4  1  0.000  0.500  0.500  1.0
  Ti  Ti5  1  0.500  0.000  0.500  1.0
  Ti  Ti6  1  0.288  0.750  0.538  1.0
  Ti  Ti7  1  0.712  0.250  0.462  1.0
  O  O8  1  0.747  0.747  0.500  1.0
  O  O9  1  0.253  0.753  0.000  1.0
  O  O10  1  0.747  0.247  0.000  1.0
  O  O11  1  0.253  0.253  0.500  1.0
  O  O12  1  0.111  0.630  0.480  1.0
  O  O13  1  0.889  0.370  0.520  1.0
  O  O14  1  0.650  0.130  0.520  1.0
  O  O15  1  0.350  0.870  0.480  1.0
  O  O16  1  0.500  0.500  0.500  1.0
  O  O17  1  0.500  0.000  0.000  1.0
[/CIF]
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