The structure described by Tm2SiO5 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Tm sites. In the first Tm site, Tm(1) is bonded in a 7-coordinate geometry to one O(4), three equivalent O(1), and three equivalent O(3) atoms. In the second Tm site, Tm(2) is bonded in a 7-coordinate geometry to one O(1), two equivalent O(2), two equivalent O(4), 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 Tm(2) and three equivalent Tm(1) atoms to form a mixture of corner and edge-sharing OTm4 tetrahedra. In the second O site, O(2) is bonded in a 3-coordinate geometry to two equivalent Tm(2) and one Si(1) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to three equivalent Tm(1) and one Si(1) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Tm(1), two equivalent Tm(2), and one Si(1) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to two equivalent Tm(2) and one Si(1) atom. is represented by the CIF card [CIF]
data_Tm2SiO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.663
_cell_length_b   6.603
_cell_length_c   9.025
_cell_angle_alpha   77.410
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   387.520
_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
  Tm  Tm0  1  0.120  0.269  0.532  1.0
  Tm  Tm1  1  0.620  0.231  0.468  1.0
  Tm  Tm2  1  0.880  0.731  0.468  1.0
  Tm  Tm3  1  0.380  0.769  0.532  1.0
  Tm  Tm4  1  0.641  0.021  0.141  1.0
  Tm  Tm5  1  0.141  0.479  0.859  1.0
  Tm  Tm6  1  0.359  0.979  0.859  1.0
  Tm  Tm7  1  0.859  0.521  0.141  1.0
  Si  Si8  1  0.095  0.007  0.202  1.0
  Si  Si9  1  0.595  0.493  0.798  1.0
  Si  Si10  1  0.905  0.993  0.798  1.0
  Si  Si11  1  0.405  0.507  0.202  1.0
  O  O12  1  0.879  0.429  0.391  1.0
  O  O13  1  0.379  0.071  0.609  1.0
  O  O14  1  0.121  0.571  0.609  1.0
  O  O15  1  0.621  0.929  0.391  1.0
  O  O16  1  0.294  0.008  0.101  1.0
  O  O17  1  0.794  0.492  0.899  1.0
  O  O18  1  0.706  0.992  0.899  1.0
  O  O19  1  0.206  0.508  0.101  1.0
  O  O20  1  0.144  0.980  0.385  1.0
  O  O21  1  0.644  0.520  0.615  1.0
  O  O22  1  0.856  0.020  0.615  1.0
  O  O23  1  0.356  0.480  0.385  1.0
  O  O24  1  0.563  0.311  0.211  1.0
  O  O25  1  0.063  0.189  0.789  1.0
  O  O26  1  0.437  0.689  0.789  1.0
  O  O27  1  0.937  0.811  0.211  1.0
  O  O28  1  0.561  0.695  0.140  1.0
  O  O29  1  0.061  0.805  0.860  1.0
  O  O30  1  0.439  0.305  0.860  1.0
  O  O31  1  0.939  0.195  0.140  1.0
[/CIF]
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The structure described by Tm2SiO5 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Tm sites. In the first Tm site, Tm(1) is bonded in a 7-coordinate geometry to one O(4), three equivalent O(1), and three equivalent O(3) atoms. In the second Tm site, Tm(2) is bonded in a 7-coordinate geometry to one O(1), two equivalent O(2), two equivalent O(4), 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 Tm(2) and three equivalent Tm(1) atoms to form a mixture of corner and edge-sharing OTm4 tetrahedra. In the second O site, O(2) is bonded in a 3-coordinate geometry to two equivalent Tm(2) and one Si(1) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to three equivalent Tm(1) and one Si(1) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Tm(1), two equivalent Tm(2), and one Si(1) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to two equivalent Tm(2) and one Si(1) atom. is represented by the CIF card [CIF]
data_Tm2SiO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.663
_cell_length_b   6.603
_cell_length_c   9.025
_cell_angle_alpha   77.410
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   387.520
_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
  Tm  Tm0  1  0.120  0.269  0.532  1.0
  Tm  Tm1  1  0.620  0.231  0.468  1.0
  Tm  Tm2  1  0.880  0.731  0.468  1.0
  Tm  Tm3  1  0.380  0.769  0.532  1.0
  Tm  Tm4  1  0.641  0.021  0.141  1.0
  Tm  Tm5  1  0.141  0.479  0.859  1.0
  Tm  Tm6  1  0.359  0.979  0.859  1.0
  Tm  Tm7  1  0.859  0.521  0.141  1.0
  Si  Si8  1  0.095  0.007  0.202  1.0
  Si  Si9  1  0.595  0.493  0.798  1.0
  Si  Si10  1  0.905  0.993  0.798  1.0
  Si  Si11  1  0.405  0.507  0.202  1.0
  O  O12  1  0.879  0.429  0.391  1.0
  O  O13  1  0.379  0.071  0.609  1.0
  O  O14  1  0.121  0.571  0.609  1.0
  O  O15  1  0.621  0.929  0.391  1.0
  O  O16  1  0.294  0.008  0.101  1.0
  O  O17  1  0.794  0.492  0.899  1.0
  O  O18  1  0.706  0.992  0.899  1.0
  O  O19  1  0.206  0.508  0.101  1.0
  O  O20  1  0.144  0.980  0.385  1.0
  O  O21  1  0.644  0.520  0.615  1.0
  O  O22  1  0.856  0.020  0.615  1.0
  O  O23  1  0.356  0.480  0.385  1.0
  O  O24  1  0.563  0.311  0.211  1.0
  O  O25  1  0.063  0.189  0.789  1.0
  O  O26  1  0.437  0.689  0.789  1.0
  O  O27  1  0.937  0.811  0.211  1.0
  O  O28  1  0.561  0.695  0.140  1.0
  O  O29  1  0.061  0.805  0.860  1.0
  O  O30  1  0.439  0.305  0.860  1.0
  O  O31  1  0.939  0.195  0.140  1.0
[/CIF]
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