The structure described by NaTiSi2O6 is Esseneite structured and crystallizes in the monoclinic C2/c space group. Na(1) is bonded in a 8-coordinate geometry to two equivalent O(1), two equivalent O(2), and four equivalent O(3) atoms. Ti(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form TiO6 octahedra that share corners with six equivalent Si(1)O4 tetrahedra and edges with two equivalent Ti(1)O6 octahedra. Si(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form SiO4 tetrahedra that share corners with three equivalent Ti(1)O6 octahedra and corners with two equivalent Si(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 31-58°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to one Na(1), one Ti(1), and one Si(1) atom. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to one Na(1), two equivalent Ti(1), and one Si(1) atom. In the third O site, O(3) is bonded in a 2-coordinate geometry to two equivalent Na(1) and two equivalent Si(1) atoms. is represented by the CIF card [CIF]
data_NaTi(SiO3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.647
_cell_length_b   6.647
_cell_length_c   5.312
_cell_angle_alpha   77.989
_cell_angle_beta   77.989
_cell_angle_gamma   83.301
_symmetry_Int_Tables_number   1
_cell_volume   223.910
_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
  Na  Na0  1  0.695  0.305  0.750  1.0
  Na  Na1  1  0.305  0.695  0.250  1.0
  Ti  Ti2  1  0.912  0.088  0.250  1.0
  Ti  Ti3  1  0.088  0.912  0.750  1.0
  Si  Si4  1  0.800  0.614  0.241  1.0
  Si  Si5  1  0.614  0.800  0.741  1.0
  Si  Si6  1  0.200  0.386  0.759  1.0
  Si  Si7  1  0.386  0.200  0.259  1.0
  O  O8  1  0.108  0.621  0.691  1.0
  O  O9  1  0.892  0.379  0.309  1.0
  O  O10  1  0.034  0.206  0.849  1.0
  O  O11  1  0.966  0.794  0.151  1.0
  O  O12  1  0.342  0.359  0.987  1.0
  O  O13  1  0.658  0.641  0.013  1.0
  O  O14  1  0.359  0.342  0.487  1.0
  O  O15  1  0.641  0.658  0.513  1.0
  O  O16  1  0.379  0.892  0.809  1.0
  O  O17  1  0.621  0.108  0.191  1.0
  O  O18  1  0.794  0.966  0.651  1.0
  O  O19  1  0.206  0.034  0.349  1.0
[/CIF]
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The structure described by NaTiSi2O6 is Esseneite structured and crystallizes in the monoclinic C2/c space group. Na(1) is bonded in a 8-coordinate geometry to two equivalent O(1), two equivalent O(2), and four equivalent O(3) atoms. Ti(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form TiO6 octahedra that share corners with six equivalent Si(1)O4 tetrahedra and edges with two equivalent Ti(1)O6 octahedra. Si(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form SiO4 tetrahedra that share corners with three equivalent Ti(1)O6 octahedra and corners with two equivalent Si(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 31-58°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to one Na(1), one Ti(1), and one Si(1) atom. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to one Na(1), two equivalent Ti(1), and one Si(1) atom. In the third O site, O(3) is bonded in a 2-coordinate geometry to two equivalent Na(1) and two equivalent Si(1) atoms. is represented by the CIF card [CIF]
data_NaTi(SiO3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.647
_cell_length_b   6.647
_cell_length_c   5.312
_cell_angle_alpha   77.989
_cell_angle_beta   77.989
_cell_angle_gamma   83.301
_symmetry_Int_Tables_number   1
_cell_volume   223.910
_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
  Na  Na0  1  0.695  0.305  0.750  1.0
  Na  Na1  1  0.305  0.695  0.250  1.0
  Ti  Ti2  1  0.912  0.088  0.250  1.0
  Ti  Ti3  1  0.088  0.912  0.750  1.0
  Si  Si4  1  0.800  0.614  0.241  1.0
  Si  Si5  1  0.614  0.800  0.741  1.0
  Si  Si6  1  0.200  0.386  0.759  1.0
  Si  Si7  1  0.386  0.200  0.259  1.0
  O  O8  1  0.108  0.621  0.691  1.0
  O  O9  1  0.892  0.379  0.309  1.0
  O  O10  1  0.034  0.206  0.849  1.0
  O  O11  1  0.966  0.794  0.151  1.0
  O  O12  1  0.342  0.359  0.987  1.0
  O  O13  1  0.658  0.641  0.013  1.0
  O  O14  1  0.359  0.342  0.487  1.0
  O  O15  1  0.641  0.658  0.513  1.0
  O  O16  1  0.379  0.892  0.809  1.0
  O  O17  1  0.621  0.108  0.191  1.0
  O  O18  1  0.794  0.966  0.651  1.0
  O  O19  1  0.206  0.034  0.349  1.0
[/CIF]
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