The crystal structure described by Y2SiO5 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded in a 9-coordinate geometry to one O(5), two equivalent O(3), three equivalent O(1), and three equivalent O(4) atoms. In the second Y site, Y(2) is bonded in a 6-coordinate geometry to one O(1), one O(3), two equivalent O(2), and two equivalent O(5) atoms. Si(1) is bonded in a tetrahedral geometry to one O(2), one O(3), one O(4), and one O(5) atom. There are five inequivalent O sites. In the first O site, O(1) is bonded to one Y(2) and three equivalent Y(1) atoms to form a mixture of edge and corner-sharing OY4 tetrahedra. In the second O site, O(2) is bonded in a 3-coordinate geometry to two equivalent Y(2) and one Si(1) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Y(2), two equivalent Y(1), and one Si(1) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to three equivalent Y(1) and one Si(1) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Y(1), two equivalent Y(2), and one Si(1) atom. is represented by the CIF file [CIF]
data_Y2SiO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.776
_cell_length_b   6.887
_cell_length_c   10.359
_cell_angle_alpha   90.000
_cell_angle_beta   119.325
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   421.451
_cell_formula_units_Z   4
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
  Y  Y0  1  0.356  0.222  0.510  1.0
  Y  Y1  1  0.144  0.722  0.490  1.0
  Y  Y2  1  0.644  0.778  0.490  1.0
  Y  Y3  1  0.856  0.278  0.510  1.0
  Y  Y4  1  0.241  0.546  0.833  1.0
  Y  Y5  1  0.259  0.046  0.167  1.0
  Y  Y6  1  0.759  0.454  0.167  1.0
  Y  Y7  1  0.741  0.954  0.833  1.0
  Si  Si8  1  0.683  0.479  0.784  1.0
  Si  Si9  1  0.817  0.979  0.216  1.0
  Si  Si10  1  0.317  0.521  0.216  1.0
  Si  Si11  1  0.183  0.021  0.784  1.0
  O  O12  1  0.469  0.915  0.602  1.0
  O  O13  1  0.031  0.415  0.398  1.0
  O  O14  1  0.531  0.085  0.398  1.0
  O  O15  1  0.969  0.585  0.602  1.0
  O  O16  1  0.126  0.030  0.921  1.0
  O  O17  1  0.374  0.530  0.079  1.0
  O  O18  1  0.874  0.970  0.079  1.0
  O  O19  1  0.626  0.470  0.921  1.0
  O  O20  1  0.240  0.233  0.733  1.0
  O  O21  1  0.260  0.733  0.267  1.0
  O  O22  1  0.760  0.767  0.267  1.0
  O  O23  1  0.740  0.267  0.733  1.0
  O  O24  1  0.445  0.530  0.629  1.0
  O  O25  1  0.055  0.030  0.371  1.0
  O  O26  1  0.555  0.470  0.371  1.0
  O  O27  1  0.945  0.970  0.629  1.0
  O  O28  1  0.628  0.150  0.177  1.0
  O  O29  1  0.872  0.650  0.823  1.0
  O  O30  1  0.372  0.850  0.823  1.0
  O  O31  1  0.128  0.350  0.177  1.0
[/CIF]
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The crystal structure described by Y2SiO5 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded in a 9-coordinate geometry to one O(5), two equivalent O(3), three equivalent O(1), and three equivalent O(4) atoms. In the second Y site, Y(2) is bonded in a 6-coordinate geometry to one O(1), one O(3), two equivalent O(2), and two equivalent O(5) atoms. Si(1) is bonded in a tetrahedral geometry to one O(2), one O(3), one O(4), and one O(5) atom. There are five inequivalent O sites. In the first O site, O(1) is bonded to one Y(2) and three equivalent Y(1) atoms to form a mixture of edge and corner-sharing OY4 tetrahedra. In the second O site, O(2) is bonded in a 3-coordinate geometry to two equivalent Y(2) and one Si(1) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Y(2), two equivalent Y(1), and one Si(1) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to three equivalent Y(1) and one Si(1) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Y(1), two equivalent Y(2), and one Si(1) atom. is represented by the CIF file [CIF]
data_Y2SiO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.776
_cell_length_b   6.887
_cell_length_c   10.359
_cell_angle_alpha   90.000
_cell_angle_beta   119.325
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   421.451
_cell_formula_units_Z   4
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
  Y  Y0  1  0.356  0.222  0.510  1.0
  Y  Y1  1  0.144  0.722  0.490  1.0
  Y  Y2  1  0.644  0.778  0.490  1.0
  Y  Y3  1  0.856  0.278  0.510  1.0
  Y  Y4  1  0.241  0.546  0.833  1.0
  Y  Y5  1  0.259  0.046  0.167  1.0
  Y  Y6  1  0.759  0.454  0.167  1.0
  Y  Y7  1  0.741  0.954  0.833  1.0
  Si  Si8  1  0.683  0.479  0.784  1.0
  Si  Si9  1  0.817  0.979  0.216  1.0
  Si  Si10  1  0.317  0.521  0.216  1.0
  Si  Si11  1  0.183  0.021  0.784  1.0
  O  O12  1  0.469  0.915  0.602  1.0
  O  O13  1  0.031  0.415  0.398  1.0
  O  O14  1  0.531  0.085  0.398  1.0
  O  O15  1  0.969  0.585  0.602  1.0
  O  O16  1  0.126  0.030  0.921  1.0
  O  O17  1  0.374  0.530  0.079  1.0
  O  O18  1  0.874  0.970  0.079  1.0
  O  O19  1  0.626  0.470  0.921  1.0
  O  O20  1  0.240  0.233  0.733  1.0
  O  O21  1  0.260  0.733  0.267  1.0
  O  O22  1  0.760  0.767  0.267  1.0
  O  O23  1  0.740  0.267  0.733  1.0
  O  O24  1  0.445  0.530  0.629  1.0
  O  O25  1  0.055  0.030  0.371  1.0
  O  O26  1  0.555  0.470  0.371  1.0
  O  O27  1  0.945  0.970  0.629  1.0
  O  O28  1  0.628  0.150  0.177  1.0
  O  O29  1  0.872  0.650  0.823  1.0
  O  O30  1  0.372  0.850  0.823  1.0
  O  O31  1  0.128  0.350  0.177  1.0
[/CIF]
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