The material described by NaTiSi2O6 is Esseneite structured and crystallizes in the triclinic P-1 space group. Na(1) is bonded in a 8-coordinate geometry to one O(1), one O(2), one O(5), one O(6), two equivalent O(3), and two equivalent O(4) atoms. Ti(1) is bonded to one O(1), one O(6), two equivalent O(2), and two equivalent O(5) atoms to form TiO6 octahedra that share corners with three equivalent Si(1)O4 tetrahedra, corners with three equivalent Si(2)O4 tetrahedra, and edges with two equivalent Ti(1)O6 octahedra. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form SiO4 tetrahedra that share corners with three equivalent Ti(1)O6 octahedra and corners with two equivalent Si(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 30-58°. In the second Si site, Si(2) is bonded to one O(3), one O(4), one O(5), and one O(6) atom 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 31-57°. There are six 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), one Si(1), and one Si(2) atom. In the fourth O site, O(4) is bonded in a 2-coordinate geometry to two equivalent Na(1), one Si(1), and one Si(2) atom. In the fifth O site, O(5) is bonded in a distorted rectangular see-saw-like geometry to one Na(1), two equivalent Ti(1), and one Si(2) atom. In the sixth O site, O(6) is bonded in a distorted T-shaped geometry to one Na(1), one Ti(1), and one Si(2) atom. is represented by the CIF file [CIF]
data_NaTi(SiO3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.315
_cell_length_b   6.651
_cell_length_c   6.654
_cell_angle_alpha   83.547
_cell_angle_beta   77.899
_cell_angle_gamma   77.959
_symmetry_Int_Tables_number   1
_cell_volume   224.344
_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  0.247  0.195  0.300  1.0
  Na  Na1  1  0.753  0.805  0.700  1.0
  Ti  Ti2  1  0.749  0.411  0.088  1.0
  Ti  Ti3  1  0.251  0.589  0.912  1.0
  Si  Si4  1  0.259  0.699  0.386  1.0
  Si  Si5  1  0.741  0.301  0.614  1.0
  Si  Si6  1  0.759  0.885  0.201  1.0
  Si  Si7  1  0.241  0.115  0.799  1.0
  O  O8  1  0.196  0.608  0.622  1.0
  O  O9  1  0.804  0.392  0.378  1.0
  O  O10  1  0.348  0.534  0.206  1.0
  O  O11  1  0.652  0.466  0.794  1.0
  O  O12  1  0.485  0.843  0.359  1.0
  O  O13  1  0.515  0.157  0.641  1.0
  O  O14  1  0.984  0.858  0.346  1.0
  O  O15  1  0.016  0.142  0.654  1.0
  O  O16  1  0.850  0.705  0.036  1.0
  O  O17  1  0.150  0.295  0.964  1.0
  O  O18  1  0.694  0.121  0.108  1.0
  O  O19  1  0.306  0.879  0.892  1.0
[/CIF]
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The material described by NaTiSi2O6 is Esseneite structured and crystallizes in the triclinic P-1 space group. Na(1) is bonded in a 8-coordinate geometry to one O(1), one O(2), one O(5), one O(6), two equivalent O(3), and two equivalent O(4) atoms. Ti(1) is bonded to one O(1), one O(6), two equivalent O(2), and two equivalent O(5) atoms to form TiO6 octahedra that share corners with three equivalent Si(1)O4 tetrahedra, corners with three equivalent Si(2)O4 tetrahedra, and edges with two equivalent Ti(1)O6 octahedra. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form SiO4 tetrahedra that share corners with three equivalent Ti(1)O6 octahedra and corners with two equivalent Si(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 30-58°. In the second Si site, Si(2) is bonded to one O(3), one O(4), one O(5), and one O(6) atom 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 31-57°. There are six 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), one Si(1), and one Si(2) atom. In the fourth O site, O(4) is bonded in a 2-coordinate geometry to two equivalent Na(1), one Si(1), and one Si(2) atom. In the fifth O site, O(5) is bonded in a distorted rectangular see-saw-like geometry to one Na(1), two equivalent Ti(1), and one Si(2) atom. In the sixth O site, O(6) is bonded in a distorted T-shaped geometry to one Na(1), one Ti(1), and one Si(2) atom. is represented by the CIF file [CIF]
data_NaTi(SiO3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.315
_cell_length_b   6.651
_cell_length_c   6.654
_cell_angle_alpha   83.547
_cell_angle_beta   77.899
_cell_angle_gamma   77.959
_symmetry_Int_Tables_number   1
_cell_volume   224.344
_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  0.247  0.195  0.300  1.0
  Na  Na1  1  0.753  0.805  0.700  1.0
  Ti  Ti2  1  0.749  0.411  0.088  1.0
  Ti  Ti3  1  0.251  0.589  0.912  1.0
  Si  Si4  1  0.259  0.699  0.386  1.0
  Si  Si5  1  0.741  0.301  0.614  1.0
  Si  Si6  1  0.759  0.885  0.201  1.0
  Si  Si7  1  0.241  0.115  0.799  1.0
  O  O8  1  0.196  0.608  0.622  1.0
  O  O9  1  0.804  0.392  0.378  1.0
  O  O10  1  0.348  0.534  0.206  1.0
  O  O11  1  0.652  0.466  0.794  1.0
  O  O12  1  0.485  0.843  0.359  1.0
  O  O13  1  0.515  0.157  0.641  1.0
  O  O14  1  0.984  0.858  0.346  1.0
  O  O15  1  0.016  0.142  0.654  1.0
  O  O16  1  0.850  0.705  0.036  1.0
  O  O17  1  0.150  0.295  0.964  1.0
  O  O18  1  0.694  0.121  0.108  1.0
  O  O19  1  0.306  0.879  0.892  1.0
[/CIF]
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