The material described by Ca2Ti2O5 crystallizes in the orthorhombic Ima2 space group. Ca(1) is bonded in a 8-coordinate geometry to one O(3), three equivalent O(2), and four equivalent O(1) 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 tetrahedra. The corner-sharing octahedral tilt angles are 11°. In the second Ti site, Ti(2) is bonded to two equivalent O(2) and two equivalent O(3) atoms to form TiO4 tetrahedra that share corners with two equivalent Ti(1)O6 octahedra and corners with two equivalent Ti(2)O4 tetrahedra. The corner-sharing octahedral tilt angles are 30°. There are three inequivalent O sites. In the first O site, O(1) is bonded to four equivalent Ca(1) and two equivalent Ti(1) atoms to form distorted OCa4Ti2 octahedra that share corners with two equivalent O(1)Ca4Ti2 octahedra, corners with four equivalent O(3)Ca2Ti2 tetrahedra, edges with two equivalent O(1)Ca4Ti2 octahedra, and faces with four equivalent O(1)Ca4Ti2 octahedra. The corner-sharing octahedral tilt angles are 1°. In the second O site, O(2) is bonded in a 5-coordinate geometry to three equivalent Ca(1), one Ti(1), and one Ti(2) atom. In the third O site, O(3) is bonded to two equivalent Ca(1) and two equivalent Ti(2) atoms to form distorted OCa2Ti2 tetrahedra that share corners with eight equivalent O(1)Ca4Ti2 octahedra and corners with two equivalent O(3)Ca2Ti2 tetrahedra. The corner-sharing octahedral tilt angles range from 20-81°. is represented by the CIF file [CIF]
data_Ca2Ti2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.604
_cell_length_b   8.604
_cell_length_c   8.604
_cell_angle_alpha   142.764
_cell_angle_beta   141.643
_cell_angle_gamma   54.528
_symmetry_Int_Tables_number   1
_cell_volume   237.542
_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
  Ca  Ca0  1  0.919  0.395  0.530  1.0
  Ca  Ca1  1  0.081  0.611  0.477  1.0
  Ca  Ca2  1  0.365  0.895  0.477  1.0
  Ca  Ca3  1  0.635  0.111  0.530  1.0
  Ti  Ti4  1  0.000  0.011  0.011  1.0
  Ti  Ti5  1  0.500  0.511  0.011  1.0
  Ti  Ti6  1  0.699  0.715  0.914  1.0
  Ti  Ti7  1  0.301  0.215  0.016  1.0
  O  O8  1  0.263  0.272  0.512  1.0
  O  O9  1  0.737  0.248  0.009  1.0
  O  O10  1  0.260  0.772  0.009  1.0
  O  O11  1  0.740  0.748  0.512  1.0
  O  O12  1  0.923  0.888  0.080  1.0
  O  O13  1  0.077  0.157  0.965  1.0
  O  O14  1  0.308  0.388  0.965  1.0
  O  O15  1  0.692  0.657  0.080  1.0
  O  O16  1  0.619  0.366  0.485  1.0
  O  O17  1  0.381  0.866  0.748  1.0
[/CIF]
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The material described by Ca2Ti2O5 crystallizes in the orthorhombic Ima2 space group. Ca(1) is bonded in a 8-coordinate geometry to one O(3), three equivalent O(2), and four equivalent O(1) 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 tetrahedra. The corner-sharing octahedral tilt angles are 11°. In the second Ti site, Ti(2) is bonded to two equivalent O(2) and two equivalent O(3) atoms to form TiO4 tetrahedra that share corners with two equivalent Ti(1)O6 octahedra and corners with two equivalent Ti(2)O4 tetrahedra. The corner-sharing octahedral tilt angles are 30°. There are three inequivalent O sites. In the first O site, O(1) is bonded to four equivalent Ca(1) and two equivalent Ti(1) atoms to form distorted OCa4Ti2 octahedra that share corners with two equivalent O(1)Ca4Ti2 octahedra, corners with four equivalent O(3)Ca2Ti2 tetrahedra, edges with two equivalent O(1)Ca4Ti2 octahedra, and faces with four equivalent O(1)Ca4Ti2 octahedra. The corner-sharing octahedral tilt angles are 1°. In the second O site, O(2) is bonded in a 5-coordinate geometry to three equivalent Ca(1), one Ti(1), and one Ti(2) atom. In the third O site, O(3) is bonded to two equivalent Ca(1) and two equivalent Ti(2) atoms to form distorted OCa2Ti2 tetrahedra that share corners with eight equivalent O(1)Ca4Ti2 octahedra and corners with two equivalent O(3)Ca2Ti2 tetrahedra. The corner-sharing octahedral tilt angles range from 20-81°. is represented by the CIF file [CIF]
data_Ca2Ti2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.604
_cell_length_b   8.604
_cell_length_c   8.604
_cell_angle_alpha   142.764
_cell_angle_beta   141.643
_cell_angle_gamma   54.528
_symmetry_Int_Tables_number   1
_cell_volume   237.542
_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
  Ca  Ca0  1  0.919  0.395  0.530  1.0
  Ca  Ca1  1  0.081  0.611  0.477  1.0
  Ca  Ca2  1  0.365  0.895  0.477  1.0
  Ca  Ca3  1  0.635  0.111  0.530  1.0
  Ti  Ti4  1  0.000  0.011  0.011  1.0
  Ti  Ti5  1  0.500  0.511  0.011  1.0
  Ti  Ti6  1  0.699  0.715  0.914  1.0
  Ti  Ti7  1  0.301  0.215  0.016  1.0
  O  O8  1  0.263  0.272  0.512  1.0
  O  O9  1  0.737  0.248  0.009  1.0
  O  O10  1  0.260  0.772  0.009  1.0
  O  O11  1  0.740  0.748  0.512  1.0
  O  O12  1  0.923  0.888  0.080  1.0
  O  O13  1  0.077  0.157  0.965  1.0
  O  O14  1  0.308  0.388  0.965  1.0
  O  O15  1  0.692  0.657  0.080  1.0
  O  O16  1  0.619  0.366  0.485  1.0
  O  O17  1  0.381  0.866  0.748  1.0
[/CIF]
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