The crystal structure described by BaTiSi3O9 crystallizes in the hexagonal P-6c2 space group. Ba(1) is bonded in a 6-coordinate geometry to six equivalent O(1) atoms. Ti(1) is bonded to six equivalent O(1) atoms to form TiO6 octahedra that share corners with six equivalent Si(1)O4 tetrahedra. Si(1) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form SiO4 tetrahedra that share corners with two equivalent Ti(1)O6 octahedra and corners with two equivalent Si(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 43°. There are two inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Ba(1), one Ti(1), and one Si(1) atom. In the second O site, O(2) is bonded in a distorted bent 120 degrees geometry to two equivalent Si(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_BaTi(SiO3)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.653
_cell_length_b   6.653
_cell_length_c   9.789
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   375.181
_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
  Ba  Ba0  1  0.667  0.333  0.500  1.0
  Ba  Ba1  1  0.667  0.333  0.000  1.0
  Ti  Ti2  1  0.333  0.667  0.500  1.0
  Ti  Ti3  1  0.333  0.667  0.000  1.0
  Si  Si4  1  0.218  0.929  0.250  1.0
  Si  Si5  1  0.218  0.289  0.750  1.0
  Si  Si6  1  0.711  0.929  0.750  1.0
  Si  Si7  1  0.711  0.782  0.250  1.0
  Si  Si8  1  0.071  0.289  0.250  1.0
  Si  Si9  1  0.071  0.782  0.750  1.0
  O  O10  1  0.088  0.658  0.613  1.0
  O  O11  1  0.342  0.912  0.387  1.0
  O  O12  1  0.570  0.912  0.613  1.0
  O  O13  1  0.342  0.430  0.887  1.0
  O  O14  1  0.570  0.912  0.887  1.0
  O  O15  1  0.088  0.658  0.887  1.0
  O  O16  1  0.570  0.658  0.113  1.0
  O  O17  1  0.088  0.430  0.113  1.0
  O  O18  1  0.254  0.192  0.250  1.0
  O  O19  1  0.939  0.746  0.250  1.0
  O  O20  1  0.808  0.061  0.250  1.0
  O  O21  1  0.808  0.746  0.750  1.0
  O  O22  1  0.570  0.658  0.387  1.0
  O  O23  1  0.254  0.061  0.750  1.0
  O  O24  1  0.939  0.192  0.750  1.0
  O  O25  1  0.088  0.430  0.387  1.0
  O  O26  1  0.342  0.912  0.113  1.0
  O  O27  1  0.342  0.430  0.613  1.0
[/CIF]
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The crystal structure described by BaTiSi3O9 crystallizes in the hexagonal P-6c2 space group. Ba(1) is bonded in a 6-coordinate geometry to six equivalent O(1) atoms. Ti(1) is bonded to six equivalent O(1) atoms to form TiO6 octahedra that share corners with six equivalent Si(1)O4 tetrahedra. Si(1) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form SiO4 tetrahedra that share corners with two equivalent Ti(1)O6 octahedra and corners with two equivalent Si(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 43°. There are two inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Ba(1), one Ti(1), and one Si(1) atom. In the second O site, O(2) is bonded in a distorted bent 120 degrees geometry to two equivalent Si(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_BaTi(SiO3)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.653
_cell_length_b   6.653
_cell_length_c   9.789
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   375.181
_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
  Ba  Ba0  1  0.667  0.333  0.500  1.0
  Ba  Ba1  1  0.667  0.333  0.000  1.0
  Ti  Ti2  1  0.333  0.667  0.500  1.0
  Ti  Ti3  1  0.333  0.667  0.000  1.0
  Si  Si4  1  0.218  0.929  0.250  1.0
  Si  Si5  1  0.218  0.289  0.750  1.0
  Si  Si6  1  0.711  0.929  0.750  1.0
  Si  Si7  1  0.711  0.782  0.250  1.0
  Si  Si8  1  0.071  0.289  0.250  1.0
  Si  Si9  1  0.071  0.782  0.750  1.0
  O  O10  1  0.088  0.658  0.613  1.0
  O  O11  1  0.342  0.912  0.387  1.0
  O  O12  1  0.570  0.912  0.613  1.0
  O  O13  1  0.342  0.430  0.887  1.0
  O  O14  1  0.570  0.912  0.887  1.0
  O  O15  1  0.088  0.658  0.887  1.0
  O  O16  1  0.570  0.658  0.113  1.0
  O  O17  1  0.088  0.430  0.113  1.0
  O  O18  1  0.254  0.192  0.250  1.0
  O  O19  1  0.939  0.746  0.250  1.0
  O  O20  1  0.808  0.061  0.250  1.0
  O  O21  1  0.808  0.746  0.750  1.0
  O  O22  1  0.570  0.658  0.387  1.0
  O  O23  1  0.254  0.061  0.750  1.0
  O  O24  1  0.939  0.192  0.750  1.0
  O  O25  1  0.088  0.430  0.387  1.0
  O  O26  1  0.342  0.912  0.113  1.0
  O  O27  1  0.342  0.430  0.613  1.0
[/CIF]
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