The crystal structure described by BaSiO3 is (Cubic) Perovskite-like structured and crystallizes in the hexagonal P6_3/mmc space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded to three equivalent O(2) and nine equivalent O(1) atoms to form BaO12 cuboctahedra that share corners with three equivalent Ba(2)O12 cuboctahedra, corners with six equivalent Ba(1)O12 cuboctahedra, corners with three equivalent Si(1)O6 octahedra, faces with three equivalent Ba(2)O12 cuboctahedra, faces with four equivalent Ba(1)O12 cuboctahedra, faces with three equivalent Si(2)O6 octahedra, and faces with four equivalent Si(1)O6 octahedra. The corner-sharing octahedral tilt angles are 6°. In the second Ba site, Ba(2) is bonded to six equivalent O(1) and six equivalent O(2) atoms to form BaO12 cuboctahedra that share corners with six equivalent Ba(1)O12 cuboctahedra, corners with six equivalent Ba(2)O12 cuboctahedra, faces with six equivalent Ba(1)O12 cuboctahedra, faces with two equivalent Si(2)O6 octahedra, and faces with six equivalent Si(1)O6 octahedra. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form SiO6 octahedra that share corners with three equivalent Ba(1)O12 cuboctahedra, corners with three equivalent Si(2)O6 octahedra, faces with three equivalent Ba(2)O12 cuboctahedra, faces with four equivalent Ba(1)O12 cuboctahedra, and  a faceface with one Si(1)O6 octahedra. The corner-sharing octahedral tilt angles are 1°. In the second Si site, Si(2) is bonded to six equivalent O(1) atoms to form SiO6 octahedra that share corners with six equivalent Si(1)O6 octahedra, faces with two equivalent Ba(2)O12 cuboctahedra, and faces with six equivalent Ba(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles are 1°. There are two inequivalent O sites. In the first O site, O(1) is bonded in a distorted linear geometry to one Ba(2), three equivalent Ba(1), one Si(1), and one Si(2) atom. In the second O site, O(2) is bonded in a distorted L-shaped geometry to two equivalent Ba(1), two equivalent Ba(2), and two equivalent Si(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_BaSiO3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.518
_cell_length_b   5.518
_cell_length_c   13.280
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   350.222
_cell_formula_units_Z   6
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  0.333  0.667  0.405  1.0
  Ba  Ba1  1  0.667  0.333  0.905  1.0
  Ba  Ba2  1  0.667  0.333  0.595  1.0
  Ba  Ba3  1  0.333  0.667  0.095  1.0
  Ba  Ba4  1  0.000  0.000  0.750  1.0
  Ba  Ba5  1  0.000  0.000  0.250  1.0
  Si  Si6  1  0.333  0.667  0.656  1.0
  Si  Si7  1  0.667  0.333  0.156  1.0
  Si  Si8  1  0.667  0.333  0.344  1.0
  Si  Si9  1  0.333  0.667  0.844  1.0
  Si  Si10  1  0.000  0.000  0.500  1.0
  Si  Si11  1  0.000  0.000  0.000  1.0
  O  O12  1  0.833  0.167  0.420  1.0
  O  O13  1  0.833  0.667  0.420  1.0
  O  O14  1  0.333  0.167  0.420  1.0
  O  O15  1  0.667  0.833  0.920  1.0
  O  O16  1  0.167  0.333  0.580  1.0
  O  O17  1  0.167  0.833  0.920  1.0
  O  O18  1  0.167  0.333  0.920  1.0
  O  O19  1  0.833  0.167  0.080  1.0
  O  O20  1  0.333  0.167  0.080  1.0
  O  O21  1  0.667  0.833  0.580  1.0
  O  O22  1  0.167  0.833  0.580  1.0
  O  O23  1  0.833  0.667  0.080  1.0
  O  O24  1  0.525  0.050  0.250  1.0
  O  O25  1  0.475  0.525  0.750  1.0
  O  O26  1  0.050  0.525  0.750  1.0
  O  O27  1  0.950  0.475  0.250  1.0
  O  O28  1  0.525  0.475  0.250  1.0
  O  O29  1  0.475  0.950  0.750  1.0
[/CIF]
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The crystal structure described by BaSiO3 is (Cubic) Perovskite-like structured and crystallizes in the hexagonal P6_3/mmc space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded to three equivalent O(2) and nine equivalent O(1) atoms to form BaO12 cuboctahedra that share corners with three equivalent Ba(2)O12 cuboctahedra, corners with six equivalent Ba(1)O12 cuboctahedra, corners with three equivalent Si(1)O6 octahedra, faces with three equivalent Ba(2)O12 cuboctahedra, faces with four equivalent Ba(1)O12 cuboctahedra, faces with three equivalent Si(2)O6 octahedra, and faces with four equivalent Si(1)O6 octahedra. The corner-sharing octahedral tilt angles are 6°. In the second Ba site, Ba(2) is bonded to six equivalent O(1) and six equivalent O(2) atoms to form BaO12 cuboctahedra that share corners with six equivalent Ba(1)O12 cuboctahedra, corners with six equivalent Ba(2)O12 cuboctahedra, faces with six equivalent Ba(1)O12 cuboctahedra, faces with two equivalent Si(2)O6 octahedra, and faces with six equivalent Si(1)O6 octahedra. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form SiO6 octahedra that share corners with three equivalent Ba(1)O12 cuboctahedra, corners with three equivalent Si(2)O6 octahedra, faces with three equivalent Ba(2)O12 cuboctahedra, faces with four equivalent Ba(1)O12 cuboctahedra, and  a faceface with one Si(1)O6 octahedra. The corner-sharing octahedral tilt angles are 1°. In the second Si site, Si(2) is bonded to six equivalent O(1) atoms to form SiO6 octahedra that share corners with six equivalent Si(1)O6 octahedra, faces with two equivalent Ba(2)O12 cuboctahedra, and faces with six equivalent Ba(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles are 1°. There are two inequivalent O sites. In the first O site, O(1) is bonded in a distorted linear geometry to one Ba(2), three equivalent Ba(1), one Si(1), and one Si(2) atom. In the second O site, O(2) is bonded in a distorted L-shaped geometry to two equivalent Ba(1), two equivalent Ba(2), and two equivalent Si(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_BaSiO3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.518
_cell_length_b   5.518
_cell_length_c   13.280
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   350.222
_cell_formula_units_Z   6
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  0.333  0.667  0.405  1.0
  Ba  Ba1  1  0.667  0.333  0.905  1.0
  Ba  Ba2  1  0.667  0.333  0.595  1.0
  Ba  Ba3  1  0.333  0.667  0.095  1.0
  Ba  Ba4  1  0.000  0.000  0.750  1.0
  Ba  Ba5  1  0.000  0.000  0.250  1.0
  Si  Si6  1  0.333  0.667  0.656  1.0
  Si  Si7  1  0.667  0.333  0.156  1.0
  Si  Si8  1  0.667  0.333  0.344  1.0
  Si  Si9  1  0.333  0.667  0.844  1.0
  Si  Si10  1  0.000  0.000  0.500  1.0
  Si  Si11  1  0.000  0.000  0.000  1.0
  O  O12  1  0.833  0.167  0.420  1.0
  O  O13  1  0.833  0.667  0.420  1.0
  O  O14  1  0.333  0.167  0.420  1.0
  O  O15  1  0.667  0.833  0.920  1.0
  O  O16  1  0.167  0.333  0.580  1.0
  O  O17  1  0.167  0.833  0.920  1.0
  O  O18  1  0.167  0.333  0.920  1.0
  O  O19  1  0.833  0.167  0.080  1.0
  O  O20  1  0.333  0.167  0.080  1.0
  O  O21  1  0.667  0.833  0.580  1.0
  O  O22  1  0.167  0.833  0.580  1.0
  O  O23  1  0.833  0.667  0.080  1.0
  O  O24  1  0.525  0.050  0.250  1.0
  O  O25  1  0.475  0.525  0.750  1.0
  O  O26  1  0.050  0.525  0.750  1.0
  O  O27  1  0.950  0.475  0.250  1.0
  O  O28  1  0.525  0.475  0.250  1.0
  O  O29  1  0.475  0.950  0.750  1.0
[/CIF]
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