The crystal structure described by BaSiO3 crystallizes in the monoclinic C2/c space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded to two equivalent O(1), two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form BaO8 hexagonal bipyramids that share corners with two equivalent Ba(2)O8 hexagonal bipyramids, corners with two equivalent Si(1)O4 tetrahedra, edges with six equivalent Ba(2)O8 hexagonal bipyramids, edges with two equivalent Si(1)O4 tetrahedra, and edges with two equivalent Si(2)O4 tetrahedra. In the second Ba site, Ba(2) is bonded to one O(3), one O(5), two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms to form distorted BaO8 hexagonal bipyramids that share  a cornercorner with one Ba(1)O8 hexagonal bipyramid,  a cornercorner with one Ba(2)O8 hexagonal bipyramid,  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(2)O4 tetrahedra, edges with three equivalent Ba(1)O8 hexagonal bipyramids, edges with three equivalent Ba(2)O8 hexagonal bipyramids,  an edgeedge with one Si(2)O4 tetrahedra, and edges with three equivalent Si(1)O4 tetrahedra. 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(5) atom to form SiO4 tetrahedra that share  a cornercorner with one Ba(1)O8 hexagonal bipyramid,  a cornercorner with one Ba(2)O8 hexagonal bipyramid,  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(2)O4 tetrahedra,  an edgeedge with one Ba(1)O8 hexagonal bipyramid, and edges with three equivalent Ba(2)O8 hexagonal bipyramids. In the second Si site, Si(2) is bonded to two equivalent O(3) and two equivalent O(4) atoms to form SiO4 tetrahedra that share corners with two equivalent Ba(2)O8 hexagonal bipyramids, corners with two equivalent Si(1)O4 tetrahedra, edges with two equivalent Ba(1)O8 hexagonal bipyramids, and edges with two equivalent Ba(2)O8 hexagonal bipyramids. There are five inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Ba(1), two equivalent Ba(2), and one Si(1) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Ba(1), two equivalent Ba(2), and one Si(1) atom. In the third O site, O(3) is bonded in a 2-coordinate geometry to one Ba(1), one Ba(2), one Si(1), and one Si(2) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Ba(1), two equivalent Ba(2), and one Si(2) atom. In the fifth O site, O(5) is bonded in a 2-coordinate geometry to 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   7.520
_cell_length_b   7.520
_cell_length_c   11.387
_cell_angle_alpha   71.265
_cell_angle_beta   71.265
_cell_angle_gamma   60.146
_symmetry_Int_Tables_number   1
_cell_volume   518.570
_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  0.000  0.500  0.500  1.0
  Ba  Ba1  1  0.326  0.850  0.501  1.0
  Ba  Ba2  1  0.150  0.674  0.999  1.0
  Ba  Ba3  1  0.850  0.326  0.001  1.0
  Ba  Ba4  1  0.674  0.150  0.499  1.0
  Ba  Ba5  1  0.500  0.000  0.000  1.0
  Si  Si6  1  0.582  0.655  0.754  1.0
  Si  Si7  1  0.820  0.180  0.750  1.0
  Si  Si8  1  0.655  0.582  0.254  1.0
  Si  Si9  1  0.345  0.418  0.746  1.0
  Si  Si10  1  0.180  0.820  0.250  1.0
  Si  Si11  1  0.418  0.345  0.246  1.0
  O  O12  1  0.626  0.802  0.622  1.0
  O  O13  1  0.537  0.712  0.887  1.0
  O  O14  1  0.784  0.417  0.752  1.0
  O  O15  1  0.802  0.626  0.122  1.0
  O  O16  1  0.712  0.537  0.387  1.0
  O  O17  1  0.968  0.121  0.618  1.0
  O  O18  1  0.381  0.619  0.750  1.0
  O  O19  1  0.879  0.032  0.882  1.0
  O  O20  1  0.417  0.784  0.252  1.0
  O  O21  1  0.583  0.216  0.748  1.0
  O  O22  1  0.121  0.968  0.118  1.0
  O  O23  1  0.619  0.381  0.250  1.0
  O  O24  1  0.032  0.879  0.382  1.0
  O  O25  1  0.288  0.463  0.613  1.0
  O  O26  1  0.198  0.374  0.878  1.0
  O  O27  1  0.216  0.583  0.248  1.0
  O  O28  1  0.463  0.288  0.113  1.0
  O  O29  1  0.374  0.198  0.378  1.0
[/CIF]
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The crystal structure described by BaSiO3 crystallizes in the monoclinic C2/c space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded to two equivalent O(1), two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form BaO8 hexagonal bipyramids that share corners with two equivalent Ba(2)O8 hexagonal bipyramids, corners with two equivalent Si(1)O4 tetrahedra, edges with six equivalent Ba(2)O8 hexagonal bipyramids, edges with two equivalent Si(1)O4 tetrahedra, and edges with two equivalent Si(2)O4 tetrahedra. In the second Ba site, Ba(2) is bonded to one O(3), one O(5), two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms to form distorted BaO8 hexagonal bipyramids that share  a cornercorner with one Ba(1)O8 hexagonal bipyramid,  a cornercorner with one Ba(2)O8 hexagonal bipyramid,  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(2)O4 tetrahedra, edges with three equivalent Ba(1)O8 hexagonal bipyramids, edges with three equivalent Ba(2)O8 hexagonal bipyramids,  an edgeedge with one Si(2)O4 tetrahedra, and edges with three equivalent Si(1)O4 tetrahedra. 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(5) atom to form SiO4 tetrahedra that share  a cornercorner with one Ba(1)O8 hexagonal bipyramid,  a cornercorner with one Ba(2)O8 hexagonal bipyramid,  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(2)O4 tetrahedra,  an edgeedge with one Ba(1)O8 hexagonal bipyramid, and edges with three equivalent Ba(2)O8 hexagonal bipyramids. In the second Si site, Si(2) is bonded to two equivalent O(3) and two equivalent O(4) atoms to form SiO4 tetrahedra that share corners with two equivalent Ba(2)O8 hexagonal bipyramids, corners with two equivalent Si(1)O4 tetrahedra, edges with two equivalent Ba(1)O8 hexagonal bipyramids, and edges with two equivalent Ba(2)O8 hexagonal bipyramids. There are five inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Ba(1), two equivalent Ba(2), and one Si(1) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Ba(1), two equivalent Ba(2), and one Si(1) atom. In the third O site, O(3) is bonded in a 2-coordinate geometry to one Ba(1), one Ba(2), one Si(1), and one Si(2) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Ba(1), two equivalent Ba(2), and one Si(2) atom. In the fifth O site, O(5) is bonded in a 2-coordinate geometry to 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   7.520
_cell_length_b   7.520
_cell_length_c   11.387
_cell_angle_alpha   71.265
_cell_angle_beta   71.265
_cell_angle_gamma   60.146
_symmetry_Int_Tables_number   1
_cell_volume   518.570
_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  0.000  0.500  0.500  1.0
  Ba  Ba1  1  0.326  0.850  0.501  1.0
  Ba  Ba2  1  0.150  0.674  0.999  1.0
  Ba  Ba3  1  0.850  0.326  0.001  1.0
  Ba  Ba4  1  0.674  0.150  0.499  1.0
  Ba  Ba5  1  0.500  0.000  0.000  1.0
  Si  Si6  1  0.582  0.655  0.754  1.0
  Si  Si7  1  0.820  0.180  0.750  1.0
  Si  Si8  1  0.655  0.582  0.254  1.0
  Si  Si9  1  0.345  0.418  0.746  1.0
  Si  Si10  1  0.180  0.820  0.250  1.0
  Si  Si11  1  0.418  0.345  0.246  1.0
  O  O12  1  0.626  0.802  0.622  1.0
  O  O13  1  0.537  0.712  0.887  1.0
  O  O14  1  0.784  0.417  0.752  1.0
  O  O15  1  0.802  0.626  0.122  1.0
  O  O16  1  0.712  0.537  0.387  1.0
  O  O17  1  0.968  0.121  0.618  1.0
  O  O18  1  0.381  0.619  0.750  1.0
  O  O19  1  0.879  0.032  0.882  1.0
  O  O20  1  0.417  0.784  0.252  1.0
  O  O21  1  0.583  0.216  0.748  1.0
  O  O22  1  0.121  0.968  0.118  1.0
  O  O23  1  0.619  0.381  0.250  1.0
  O  O24  1  0.032  0.879  0.382  1.0
  O  O25  1  0.288  0.463  0.613  1.0
  O  O26  1  0.198  0.374  0.878  1.0
  O  O27  1  0.216  0.583  0.248  1.0
  O  O28  1  0.463  0.288  0.113  1.0
  O  O29  1  0.374  0.198  0.378  1.0
[/CIF]
.