The compound described by Ba3SiO5 crystallizes in the tetragonal I4/mcm space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 8-coordinate geometry to two equivalent O(2) and six equivalent O(1) atoms. In the second Ba site, Ba(2) is bonded in a 10-coordinate geometry to two equivalent O(2) and eight equivalent O(1) atoms. Si(1) is bonded in a tetrahedral geometry to four equivalent O(1) atoms. There are two inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to two equivalent Ba(2), three equivalent Ba(1), and one Si(1) atom. In the second O site, O(2) is bonded to two equivalent Ba(2) and four equivalent Ba(1) atoms to form corner-sharing OBa6 octahedra. The corner-sharing octahedral tilt angles range from 0-31°. is represented by the CIF file [CIF]
data_Ba3SiO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.679
_cell_length_b   7.679
_cell_length_c   7.679
_cell_angle_alpha   122.901
_cell_angle_beta   122.901
_cell_angle_gamma   85.045
_symmetry_Int_Tables_number   1
_cell_volume   304.926
_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  0.818  0.318  0.136  1.0
  Ba  Ba1  1  0.318  0.182  0.500  1.0
  Ba  Ba2  1  0.682  0.818  0.500  1.0
  Ba  Ba3  1  0.182  0.682  0.864  1.0
  Ba  Ba4  1  0.250  0.250  0.000  1.0
  Ba  Ba5  1  0.750  0.750  0.000  1.0
  Si  Si6  1  0.750  0.250  0.500  1.0
  Si  Si7  1  0.250  0.750  0.500  1.0
  O  O8  1  0.210  0.710  0.247  1.0
  O  O9  1  0.536  0.036  0.247  1.0
  O  O10  1  0.790  0.290  0.753  1.0
  O  O11  1  0.290  0.536  0.500  1.0
  O  O12  1  0.036  0.790  0.500  1.0
  O  O13  1  0.710  0.464  0.500  1.0
  O  O14  1  0.964  0.210  0.500  1.0
  O  O15  1  0.464  0.964  0.753  1.0
  O  O16  1  0.500  0.500  1.000  1.0
  O  O17  1  0.000  0.000  0.000  1.0
[/CIF]
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The compound described by Ba3SiO5 crystallizes in the tetragonal I4/mcm space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 8-coordinate geometry to two equivalent O(2) and six equivalent O(1) atoms. In the second Ba site, Ba(2) is bonded in a 10-coordinate geometry to two equivalent O(2) and eight equivalent O(1) atoms. Si(1) is bonded in a tetrahedral geometry to four equivalent O(1) atoms. There are two inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to two equivalent Ba(2), three equivalent Ba(1), and one Si(1) atom. In the second O site, O(2) is bonded to two equivalent Ba(2) and four equivalent Ba(1) atoms to form corner-sharing OBa6 octahedra. The corner-sharing octahedral tilt angles range from 0-31°. is represented by the CIF file [CIF]
data_Ba3SiO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.679
_cell_length_b   7.679
_cell_length_c   7.679
_cell_angle_alpha   122.901
_cell_angle_beta   122.901
_cell_angle_gamma   85.045
_symmetry_Int_Tables_number   1
_cell_volume   304.926
_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  0.818  0.318  0.136  1.0
  Ba  Ba1  1  0.318  0.182  0.500  1.0
  Ba  Ba2  1  0.682  0.818  0.500  1.0
  Ba  Ba3  1  0.182  0.682  0.864  1.0
  Ba  Ba4  1  0.250  0.250  0.000  1.0
  Ba  Ba5  1  0.750  0.750  0.000  1.0
  Si  Si6  1  0.750  0.250  0.500  1.0
  Si  Si7  1  0.250  0.750  0.500  1.0
  O  O8  1  0.210  0.710  0.247  1.0
  O  O9  1  0.536  0.036  0.247  1.0
  O  O10  1  0.790  0.290  0.753  1.0
  O  O11  1  0.290  0.536  0.500  1.0
  O  O12  1  0.036  0.790  0.500  1.0
  O  O13  1  0.710  0.464  0.500  1.0
  O  O14  1  0.964  0.210  0.500  1.0
  O  O15  1  0.464  0.964  0.753  1.0
  O  O16  1  0.500  0.500  1.000  1.0
  O  O17  1  0.000  0.000  0.000  1.0
[/CIF]
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