The material described by Li6Ti2O7 crystallizes in the tetragonal P4_2nm space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded in a 5-coordinate geometry to two equivalent O(3) and three equivalent O(2) atoms. In the second Li site, Li(2) is bonded to one O(3), two equivalent O(1), and two equivalent O(2) atoms to form LiO5 trigonal bipyramids that share  a cornercorner with one Ti(1)O6 octahedra, corners with four equivalent Li(2)O5 trigonal bipyramids, edges with four equivalent Ti(1)O6 octahedra, and  an edgeedge with one Li(2)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 2°. Ti(1) is bonded to one O(1), one O(3), and four equivalent O(2) atoms to form TiO6 octahedra that share  a cornercorner with one Ti(1)O6 octahedra,  a cornercorner with one Li(2)O5 trigonal bipyramid, edges with two equivalent Ti(1)O6 octahedra, and edges with four equivalent Li(2)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 2°. There are three inequivalent O sites. In the first O site, O(1) is bonded to four equivalent Li(2) and two equivalent Ti(1) atoms to form OLi4Ti2 octahedra that share corners with six equivalent O(3)Li5Ti octahedra, edges with two equivalent O(1)Li4Ti2 octahedra, and edges with eight equivalent O(2)Li4Ti2 octahedra. The corner-sharing octahedral tilt angles range from 3-51°. In the second O site, O(2) is bonded to one Li(2), three equivalent Li(1), and two equivalent Ti(1) atoms to form OLi4Ti2 octahedra that share corners with two equivalent O(3)Li5Ti octahedra, corners with seven equivalent O(2)Li4Ti2 octahedra, edges with two equivalent O(1)Li4Ti2 octahedra, edges with two equivalent O(3)Li5Ti octahedra, edges with three equivalent O(2)Li4Ti2 octahedra, and  a faceface with one O(3)Li5Ti octahedra. The corner-sharing octahedral tilt angles range from 4-47°. In the third O site, O(3) is bonded to one Li(2), four equivalent Li(1), and one Ti(1) atom to form OLi5Ti octahedra that share corners with three equivalent O(1)Li4Ti2 octahedra, corners with four equivalent O(2)Li4Ti2 octahedra, edges with two equivalent O(3)Li5Ti octahedra, edges with four equivalent O(2)Li4Ti2 octahedra, and faces with two equivalent O(2)Li4Ti2 octahedra. The corner-sharing octahedral tilt angles range from 3-51°. is represented by the CIF card [CIF]
data_Li6Ti2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.089
_cell_length_b   10.089
_cell_length_c   2.963
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   301.609
_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
  Li  Li0  1  0.300  0.108  0.032  1.0
  Li  Li1  1  0.085  0.085  0.535  1.0
  Li  Li2  1  0.608  0.200  0.532  1.0
  Li  Li3  1  0.108  0.300  0.032  1.0
  Li  Li4  1  0.585  0.415  0.035  1.0
  Li  Li5  1  0.800  0.392  0.532  1.0
  Li  Li6  1  0.200  0.608  0.532  1.0
  Li  Li7  1  0.415  0.585  0.035  1.0
  Li  Li8  1  0.892  0.700  0.032  1.0
  Li  Li9  1  0.392  0.800  0.532  1.0
  Li  Li10  1  0.915  0.915  0.535  1.0
  Li  Li11  1  0.700  0.892  0.032  1.0
  Ti  Ti12  1  0.847  0.153  0.048  1.0
  Ti  Ti13  1  0.347  0.347  0.548  1.0
  Ti  Ti14  1  0.653  0.653  0.548  1.0
  Ti  Ti15  1  0.153  0.847  0.048  1.0
  O  O16  1  0.000  0.000  0.035  1.0
  O  O17  1  0.755  0.053  0.530  1.0
  O  O18  1  0.447  0.255  0.030  1.0
  O  O19  1  0.218  0.218  0.532  1.0
  O  O20  1  0.718  0.282  0.032  1.0
  O  O21  1  0.947  0.245  0.530  1.0
  O  O22  1  0.255  0.447  0.030  1.0
  O  O23  1  0.500  0.500  0.535  1.0
  O  O24  1  0.745  0.553  0.030  1.0
  O  O25  1  0.053  0.755  0.530  1.0
  O  O26  1  0.282  0.718  0.032  1.0
  O  O27  1  0.782  0.782  0.532  1.0
  O  O28  1  0.553  0.745  0.030  1.0
  O  O29  1  0.245  0.947  0.530  1.0
[/CIF]
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The material described by Li6Ti2O7 crystallizes in the tetragonal P4_2nm space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded in a 5-coordinate geometry to two equivalent O(3) and three equivalent O(2) atoms. In the second Li site, Li(2) is bonded to one O(3), two equivalent O(1), and two equivalent O(2) atoms to form LiO5 trigonal bipyramids that share  a cornercorner with one Ti(1)O6 octahedra, corners with four equivalent Li(2)O5 trigonal bipyramids, edges with four equivalent Ti(1)O6 octahedra, and  an edgeedge with one Li(2)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 2°. Ti(1) is bonded to one O(1), one O(3), and four equivalent O(2) atoms to form TiO6 octahedra that share  a cornercorner with one Ti(1)O6 octahedra,  a cornercorner with one Li(2)O5 trigonal bipyramid, edges with two equivalent Ti(1)O6 octahedra, and edges with four equivalent Li(2)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 2°. There are three inequivalent O sites. In the first O site, O(1) is bonded to four equivalent Li(2) and two equivalent Ti(1) atoms to form OLi4Ti2 octahedra that share corners with six equivalent O(3)Li5Ti octahedra, edges with two equivalent O(1)Li4Ti2 octahedra, and edges with eight equivalent O(2)Li4Ti2 octahedra. The corner-sharing octahedral tilt angles range from 3-51°. In the second O site, O(2) is bonded to one Li(2), three equivalent Li(1), and two equivalent Ti(1) atoms to form OLi4Ti2 octahedra that share corners with two equivalent O(3)Li5Ti octahedra, corners with seven equivalent O(2)Li4Ti2 octahedra, edges with two equivalent O(1)Li4Ti2 octahedra, edges with two equivalent O(3)Li5Ti octahedra, edges with three equivalent O(2)Li4Ti2 octahedra, and  a faceface with one O(3)Li5Ti octahedra. The corner-sharing octahedral tilt angles range from 4-47°. In the third O site, O(3) is bonded to one Li(2), four equivalent Li(1), and one Ti(1) atom to form OLi5Ti octahedra that share corners with three equivalent O(1)Li4Ti2 octahedra, corners with four equivalent O(2)Li4Ti2 octahedra, edges with two equivalent O(3)Li5Ti octahedra, edges with four equivalent O(2)Li4Ti2 octahedra, and faces with two equivalent O(2)Li4Ti2 octahedra. The corner-sharing octahedral tilt angles range from 3-51°. is represented by the CIF card [CIF]
data_Li6Ti2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.089
_cell_length_b   10.089
_cell_length_c   2.963
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   301.609
_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
  Li  Li0  1  0.300  0.108  0.032  1.0
  Li  Li1  1  0.085  0.085  0.535  1.0
  Li  Li2  1  0.608  0.200  0.532  1.0
  Li  Li3  1  0.108  0.300  0.032  1.0
  Li  Li4  1  0.585  0.415  0.035  1.0
  Li  Li5  1  0.800  0.392  0.532  1.0
  Li  Li6  1  0.200  0.608  0.532  1.0
  Li  Li7  1  0.415  0.585  0.035  1.0
  Li  Li8  1  0.892  0.700  0.032  1.0
  Li  Li9  1  0.392  0.800  0.532  1.0
  Li  Li10  1  0.915  0.915  0.535  1.0
  Li  Li11  1  0.700  0.892  0.032  1.0
  Ti  Ti12  1  0.847  0.153  0.048  1.0
  Ti  Ti13  1  0.347  0.347  0.548  1.0
  Ti  Ti14  1  0.653  0.653  0.548  1.0
  Ti  Ti15  1  0.153  0.847  0.048  1.0
  O  O16  1  0.000  0.000  0.035  1.0
  O  O17  1  0.755  0.053  0.530  1.0
  O  O18  1  0.447  0.255  0.030  1.0
  O  O19  1  0.218  0.218  0.532  1.0
  O  O20  1  0.718  0.282  0.032  1.0
  O  O21  1  0.947  0.245  0.530  1.0
  O  O22  1  0.255  0.447  0.030  1.0
  O  O23  1  0.500  0.500  0.535  1.0
  O  O24  1  0.745  0.553  0.030  1.0
  O  O25  1  0.053  0.755  0.530  1.0
  O  O26  1  0.282  0.718  0.032  1.0
  O  O27  1  0.782  0.782  0.532  1.0
  O  O28  1  0.553  0.745  0.030  1.0
  O  O29  1  0.245  0.947  0.530  1.0
[/CIF]
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