The material described by Ti8O13 crystallizes in the trigonal R-3 space group. There are two inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to one O(1), two equivalent O(2), and three equivalent O(3) atoms to form a mixture of edge and corner-sharing TiO6 octahedra. The corner-sharing octahedral tilt angles range from 0-18°. In the second Ti site, Ti(2) is bonded to three equivalent O(2) and three equivalent O(3) atoms to form a mixture of distorted edge and corner-sharing TiO6 octahedra. The corner-sharing octahedral tilt angles are 14°. There are three inequivalent O sites. In the first O site, O(1) is bonded to six equivalent Ti(1) atoms to form a mixture of edge and corner-sharing OTi6 octahedra. In the second O site, O(2) is bonded in a T-shaped geometry to one Ti(2) and two equivalent Ti(1) atoms. In the third O site, O(3) is bonded to one Ti(2) and three equivalent Ti(1) atoms to form OTi4 trigonal pyramids that share  a cornercorner with one O(1)Ti6 octahedra, corners with two equivalent O(3)Ti4 trigonal pyramids,  an edgeedge with one O(1)Ti6 octahedra, and edges with three equivalent O(3)Ti4 trigonal pyramids. The corner-sharing octahedral tilt angles are 14°. is represented by the CIF card [CIF]
data_Ti8O13
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.461
_cell_length_b   6.461
_cell_length_c   6.461
_cell_angle_alpha   73.612
_cell_angle_beta   73.612
_cell_angle_gamma   73.612
_symmetry_Int_Tables_number   1
_cell_volume   242.123
_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
  Ti  Ti0  1  0.058  0.314  0.876  1.0
  Ti  Ti1  1  0.277  0.277  0.277  1.0
  Ti  Ti2  1  0.314  0.876  0.058  1.0
  Ti  Ti3  1  0.124  0.942  0.686  1.0
  Ti  Ti4  1  0.876  0.058  0.314  1.0
  Ti  Ti5  1  0.686  0.124  0.942  1.0
  Ti  Ti6  1  0.723  0.723  0.723  1.0
  Ti  Ti7  1  0.942  0.686  0.124  1.0
  O  O8  1  0.000  0.000  0.000  1.0
  O  O9  1  0.172  0.257  0.580  1.0
  O  O10  1  0.040  0.643  0.798  1.0
  O  O11  1  0.257  0.580  0.172  1.0
  O  O12  1  0.202  0.960  0.357  1.0
  O  O13  1  0.357  0.202  0.960  1.0
  O  O14  1  0.580  0.172  0.257  1.0
  O  O15  1  0.420  0.828  0.743  1.0
  O  O16  1  0.643  0.798  0.040  1.0
  O  O17  1  0.798  0.040  0.643  1.0
  O  O18  1  0.743  0.420  0.828  1.0
  O  O19  1  0.960  0.357  0.202  1.0
  O  O20  1  0.828  0.743  0.420  1.0
[/CIF]
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The material described by Ti8O13 crystallizes in the trigonal R-3 space group. There are two inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to one O(1), two equivalent O(2), and three equivalent O(3) atoms to form a mixture of edge and corner-sharing TiO6 octahedra. The corner-sharing octahedral tilt angles range from 0-18°. In the second Ti site, Ti(2) is bonded to three equivalent O(2) and three equivalent O(3) atoms to form a mixture of distorted edge and corner-sharing TiO6 octahedra. The corner-sharing octahedral tilt angles are 14°. There are three inequivalent O sites. In the first O site, O(1) is bonded to six equivalent Ti(1) atoms to form a mixture of edge and corner-sharing OTi6 octahedra. In the second O site, O(2) is bonded in a T-shaped geometry to one Ti(2) and two equivalent Ti(1) atoms. In the third O site, O(3) is bonded to one Ti(2) and three equivalent Ti(1) atoms to form OTi4 trigonal pyramids that share  a cornercorner with one O(1)Ti6 octahedra, corners with two equivalent O(3)Ti4 trigonal pyramids,  an edgeedge with one O(1)Ti6 octahedra, and edges with three equivalent O(3)Ti4 trigonal pyramids. The corner-sharing octahedral tilt angles are 14°. is represented by the CIF card [CIF]
data_Ti8O13
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.461
_cell_length_b   6.461
_cell_length_c   6.461
_cell_angle_alpha   73.612
_cell_angle_beta   73.612
_cell_angle_gamma   73.612
_symmetry_Int_Tables_number   1
_cell_volume   242.123
_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
  Ti  Ti0  1  0.058  0.314  0.876  1.0
  Ti  Ti1  1  0.277  0.277  0.277  1.0
  Ti  Ti2  1  0.314  0.876  0.058  1.0
  Ti  Ti3  1  0.124  0.942  0.686  1.0
  Ti  Ti4  1  0.876  0.058  0.314  1.0
  Ti  Ti5  1  0.686  0.124  0.942  1.0
  Ti  Ti6  1  0.723  0.723  0.723  1.0
  Ti  Ti7  1  0.942  0.686  0.124  1.0
  O  O8  1  0.000  0.000  0.000  1.0
  O  O9  1  0.172  0.257  0.580  1.0
  O  O10  1  0.040  0.643  0.798  1.0
  O  O11  1  0.257  0.580  0.172  1.0
  O  O12  1  0.202  0.960  0.357  1.0
  O  O13  1  0.357  0.202  0.960  1.0
  O  O14  1  0.580  0.172  0.257  1.0
  O  O15  1  0.420  0.828  0.743  1.0
  O  O16  1  0.643  0.798  0.040  1.0
  O  O17  1  0.798  0.040  0.643  1.0
  O  O18  1  0.743  0.420  0.828  1.0
  O  O19  1  0.960  0.357  0.202  1.0
  O  O20  1  0.828  0.743  0.420  1.0
[/CIF]
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