The material structure described by BaSi2O5 crystallizes in the monoclinic C2/c space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 9-coordinate geometry to one O(1), one O(3), one O(4), one O(8), two equivalent O(7), and three equivalent O(2) atoms. In the second Ba site, Ba(2) is bonded in a distorted body-centered cubic geometry to two equivalent O(5), two equivalent O(7), and four equivalent O(4) atoms. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form corner-sharing SiO4 tetrahedra. In the second Si site, Si(2) is bonded to one O(3), one O(4), one O(5), and one O(8) atom to form corner-sharing SiO4 tetrahedra. In the third Si site, Si(3) is bonded to one O(5), one O(6), one O(7), and one O(8) atom to form corner-sharing SiO4 tetrahedra. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a 2-coordinate geometry to one Ba(1) and two equivalent Si(1) atoms. In the second O site, O(2) is bonded in a distorted single-bond geometry to three equivalent Ba(1) and one Si(1) atom. In the third O site, O(3) is bonded in a distorted bent 150 degrees geometry to one Ba(1), one Si(1), and one Si(2) atom. In the fourth O site, O(4) is bonded in a distorted single-bond 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 distorted bent 150 degrees geometry to one Ba(2), one Si(2), and one Si(3) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to two equivalent Si(3) atoms. In the seventh O site, O(7) is bonded in a distorted single-bond geometry to one Ba(2), two equivalent Ba(1), and one Si(3) atom. In the eighth O site, O(8) is bonded in a distorted bent 120 degrees geometry to one Ba(1), one Si(2), and one Si(3) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_BaSi2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.657
_cell_length_b   11.843
_cell_length_c   13.664
_cell_angle_alpha   97.365
_cell_angle_beta   90.000
_cell_angle_gamma   101.340
_symmetry_Int_Tables_number   1
_cell_volume   732.599
_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  0.710  0.327  0.436  1.0
  Ba  Ba1  1  0.382  0.673  0.064  1.0
  Ba  Ba2  1  0.290  0.673  0.564  1.0
  Ba  Ba3  1  0.618  0.327  0.936  1.0
  Ba  Ba4  1  0.000  0.000  0.000  1.0
  Ba  Ba5  1  0.000  0.000  0.500  1.0
  Si  Si6  1  0.860  0.474  0.179  1.0
  Si  Si7  1  0.385  0.526  0.321  1.0
  Si  Si8  1  0.140  0.526  0.821  1.0
  Si  Si9  1  0.615  0.474  0.679  1.0
  Si  Si10  1  0.691  0.205  0.150  1.0
  Si  Si11  1  0.486  0.795  0.350  1.0
  Si  Si12  1  0.309  0.795  0.850  1.0
  Si  Si13  1  0.514  0.205  0.650  1.0
  Si  Si14  1  0.173  0.133  0.271  1.0
  Si  Si15  1  0.040  0.867  0.229  1.0
  Si  Si16  1  0.827  0.867  0.729  1.0
  Si  Si17  1  0.960  0.133  0.771  1.0
  O  O18  1  0.671  0.474  0.280  1.0
  O  O19  1  0.196  0.526  0.220  1.0
  O  O20  1  0.329  0.526  0.720  1.0
  O  O21  1  0.804  0.474  0.780  1.0
  O  O22  1  0.778  0.542  0.094  1.0
  O  O23  1  0.237  0.458  0.406  1.0
  O  O24  1  0.222  0.458  0.906  1.0
  O  O25  1  0.763  0.542  0.594  1.0
  O  O26  1  0.842  0.338  0.135  1.0
  O  O27  1  0.504  0.662  0.365  1.0
  O  O28  1  0.158  0.662  0.865  1.0
  O  O29  1  0.496  0.338  0.635  1.0
  O  O30  1  0.538  0.141  0.050  1.0
  O  O31  1  0.398  0.859  0.450  1.0
  O  O32  1  0.462  0.859  0.950  1.0
  O  O33  1  0.602  0.141  0.550  1.0
  O  O34  1  0.950  0.140  0.180  1.0
  O  O35  1  0.809  0.860  0.320  1.0
  O  O36  1  0.774  0.000  0.750  1.0
  O  O37  1  0.226  0.000  0.250  1.0
  O  O38  1  0.094  0.173  0.879  1.0
  O  O39  1  0.920  0.827  0.621  1.0
  O  O40  1  0.906  0.827  0.121  1.0
  O  O41  1  0.080  0.173  0.379  1.0
  O  O42  1  0.727  0.215  0.747  1.0
  O  O43  1  0.513  0.785  0.753  1.0
  O  O44  1  0.273  0.785  0.253  1.0
  O  O45  1  0.487  0.215  0.247  1.0
  O  O46  1  0.191  0.140  0.680  1.0
  O  O47  1  0.050  0.860  0.820  1.0
[/CIF]
.
The material structure described by BaSi2O5 crystallizes in the monoclinic C2/c space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 9-coordinate geometry to one O(1), one O(3), one O(4), one O(8), two equivalent O(7), and three equivalent O(2) atoms. In the second Ba site, Ba(2) is bonded in a distorted body-centered cubic geometry to two equivalent O(5), two equivalent O(7), and four equivalent O(4) atoms. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form corner-sharing SiO4 tetrahedra. In the second Si site, Si(2) is bonded to one O(3), one O(4), one O(5), and one O(8) atom to form corner-sharing SiO4 tetrahedra. In the third Si site, Si(3) is bonded to one O(5), one O(6), one O(7), and one O(8) atom to form corner-sharing SiO4 tetrahedra. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a 2-coordinate geometry to one Ba(1) and two equivalent Si(1) atoms. In the second O site, O(2) is bonded in a distorted single-bond geometry to three equivalent Ba(1) and one Si(1) atom. In the third O site, O(3) is bonded in a distorted bent 150 degrees geometry to one Ba(1), one Si(1), and one Si(2) atom. In the fourth O site, O(4) is bonded in a distorted single-bond 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 distorted bent 150 degrees geometry to one Ba(2), one Si(2), and one Si(3) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to two equivalent Si(3) atoms. In the seventh O site, O(7) is bonded in a distorted single-bond geometry to one Ba(2), two equivalent Ba(1), and one Si(3) atom. In the eighth O site, O(8) is bonded in a distorted bent 120 degrees geometry to one Ba(1), one Si(2), and one Si(3) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_BaSi2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.657
_cell_length_b   11.843
_cell_length_c   13.664
_cell_angle_alpha   97.365
_cell_angle_beta   90.000
_cell_angle_gamma   101.340
_symmetry_Int_Tables_number   1
_cell_volume   732.599
_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  0.710  0.327  0.436  1.0
  Ba  Ba1  1  0.382  0.673  0.064  1.0
  Ba  Ba2  1  0.290  0.673  0.564  1.0
  Ba  Ba3  1  0.618  0.327  0.936  1.0
  Ba  Ba4  1  0.000  0.000  0.000  1.0
  Ba  Ba5  1  0.000  0.000  0.500  1.0
  Si  Si6  1  0.860  0.474  0.179  1.0
  Si  Si7  1  0.385  0.526  0.321  1.0
  Si  Si8  1  0.140  0.526  0.821  1.0
  Si  Si9  1  0.615  0.474  0.679  1.0
  Si  Si10  1  0.691  0.205  0.150  1.0
  Si  Si11  1  0.486  0.795  0.350  1.0
  Si  Si12  1  0.309  0.795  0.850  1.0
  Si  Si13  1  0.514  0.205  0.650  1.0
  Si  Si14  1  0.173  0.133  0.271  1.0
  Si  Si15  1  0.040  0.867  0.229  1.0
  Si  Si16  1  0.827  0.867  0.729  1.0
  Si  Si17  1  0.960  0.133  0.771  1.0
  O  O18  1  0.671  0.474  0.280  1.0
  O  O19  1  0.196  0.526  0.220  1.0
  O  O20  1  0.329  0.526  0.720  1.0
  O  O21  1  0.804  0.474  0.780  1.0
  O  O22  1  0.778  0.542  0.094  1.0
  O  O23  1  0.237  0.458  0.406  1.0
  O  O24  1  0.222  0.458  0.906  1.0
  O  O25  1  0.763  0.542  0.594  1.0
  O  O26  1  0.842  0.338  0.135  1.0
  O  O27  1  0.504  0.662  0.365  1.0
  O  O28  1  0.158  0.662  0.865  1.0
  O  O29  1  0.496  0.338  0.635  1.0
  O  O30  1  0.538  0.141  0.050  1.0
  O  O31  1  0.398  0.859  0.450  1.0
  O  O32  1  0.462  0.859  0.950  1.0
  O  O33  1  0.602  0.141  0.550  1.0
  O  O34  1  0.950  0.140  0.180  1.0
  O  O35  1  0.809  0.860  0.320  1.0
  O  O36  1  0.774  0.000  0.750  1.0
  O  O37  1  0.226  0.000  0.250  1.0
  O  O38  1  0.094  0.173  0.879  1.0
  O  O39  1  0.920  0.827  0.621  1.0
  O  O40  1  0.906  0.827  0.121  1.0
  O  O41  1  0.080  0.173  0.379  1.0
  O  O42  1  0.727  0.215  0.747  1.0
  O  O43  1  0.513  0.785  0.753  1.0
  O  O44  1  0.273  0.785  0.253  1.0
  O  O45  1  0.487  0.215  0.247  1.0
  O  O46  1  0.191  0.140  0.680  1.0
  O  O47  1  0.050  0.860  0.820  1.0
[/CIF]
.