The material described by B2Si2O5 crystallizes in the tetragonal P4/mmm space group. B(1) is bonded to one O(2) and four equivalent O(1) atoms to form distorted BO5 square pyramids that share corners with five equivalent B(1)O5 square pyramids and faces with four equivalent Si(2)O12 cuboctahedra. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a body-centered cubic geometry to eight equivalent O(1) atoms. In the second Si site, Si(2) is bonded to four equivalent O(2) and eight equivalent O(1) atoms to form SiO12 cuboctahedra that share corners with four equivalent Si(2)O12 cuboctahedra, faces with four equivalent Si(2)O12 cuboctahedra, and faces with eight equivalent B(1)O5 square pyramids. There are two inequivalent O sites. In the first O site, O(1) is bonded in a 2-coordinate geometry to two equivalent B(1), two equivalent Si(1), and two equivalent Si(2) atoms. In the second O site, O(2) is bonded in a linear geometry to two equivalent B(1) and four equivalent Si(2) atoms. is represented by the CIF card [CIF]
data_Si2B2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.384
_cell_length_b   3.384
_cell_length_c   6.795
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   77.827
_cell_formula_units_Z   1
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
  Si  Si0  1  0.000  0.000  0.000  1.0
  Si  Si1  1  0.000  0.000  0.500  1.0
  B  B2  1  0.500  0.500  0.288  1.0
  B  B3  1  0.500  0.500  0.712  1.0
  O  O4  1  0.500  0.000  0.233  1.0
  O  O5  1  0.500  0.000  0.767  1.0
  O  O6  1  0.500  0.500  0.500  1.0
  O  O7  1  0.000  0.500  0.233  1.0
  O  O8  1  0.000  0.500  0.767  1.0
[/CIF]
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The material described by B2Si2O5 crystallizes in the tetragonal P4/mmm space group. B(1) is bonded to one O(2) and four equivalent O(1) atoms to form distorted BO5 square pyramids that share corners with five equivalent B(1)O5 square pyramids and faces with four equivalent Si(2)O12 cuboctahedra. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a body-centered cubic geometry to eight equivalent O(1) atoms. In the second Si site, Si(2) is bonded to four equivalent O(2) and eight equivalent O(1) atoms to form SiO12 cuboctahedra that share corners with four equivalent Si(2)O12 cuboctahedra, faces with four equivalent Si(2)O12 cuboctahedra, and faces with eight equivalent B(1)O5 square pyramids. There are two inequivalent O sites. In the first O site, O(1) is bonded in a 2-coordinate geometry to two equivalent B(1), two equivalent Si(1), and two equivalent Si(2) atoms. In the second O site, O(2) is bonded in a linear geometry to two equivalent B(1) and four equivalent Si(2) atoms. is represented by the CIF card [CIF]
data_Si2B2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.384
_cell_length_b   3.384
_cell_length_c   6.795
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   77.827
_cell_formula_units_Z   1
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
  Si  Si0  1  0.000  0.000  0.000  1.0
  Si  Si1  1  0.000  0.000  0.500  1.0
  B  B2  1  0.500  0.500  0.288  1.0
  B  B3  1  0.500  0.500  0.712  1.0
  O  O4  1  0.500  0.000  0.233  1.0
  O  O5  1  0.500  0.000  0.767  1.0
  O  O6  1  0.500  0.500  0.500  1.0
  O  O7  1  0.000  0.500  0.233  1.0
  O  O8  1  0.000  0.500  0.767  1.0
[/CIF]
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