The material structure described by Sm2SiSeO4 crystallizes in the orthorhombic Pbcm space group. There are two inequivalent Sm sites. In the first Sm site, Sm(1) is bonded in a 6-coordinate geometry to two equivalent Se(1), two equivalent O(2), and four equivalent O(1) atoms. In the second Sm site, Sm(2) is bonded in a 8-coordinate geometry to two equivalent Se(1), two equivalent O(1), and four equivalent O(2) atoms. Si(1) is bonded in a tetrahedral geometry to two equivalent O(1) and two equivalent O(2) atoms. Se(1) is bonded in a 4-coordinate geometry to two equivalent Sm(1) and two equivalent Sm(2) atoms. There are two inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Sm(2), two equivalent Sm(1), and one Si(1) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Sm(1), two equivalent Sm(2), and one Si(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sm2SiSeO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.181
_cell_length_b   7.148
_cell_length_c   11.025
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   487.103
_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
  Sm  Sm0  1  0.609  0.250  0.500  1.0
  Sm  Sm1  1  0.609  0.250  0.000  1.0
  Sm  Sm2  1  0.391  0.750  0.500  1.0
  Sm  Sm3  1  0.391  0.750  0.000  1.0
  Sm  Sm4  1  0.868  0.533  0.750  1.0
  Sm  Sm5  1  0.868  0.967  0.250  1.0
  Sm  Sm6  1  0.132  0.033  0.750  1.0
  Sm  Sm7  1  0.132  0.467  0.250  1.0
  Si  Si8  1  0.114  0.250  0.500  1.0
  Si  Si9  1  0.886  0.750  0.500  1.0
  Si  Si10  1  0.886  0.750  0.000  1.0
  Si  Si11  1  0.114  0.250  0.000  1.0
  Se  Se12  1  0.573  0.879  0.750  1.0
  Se  Se13  1  0.573  0.621  0.250  1.0
  Se  Se14  1  0.427  0.379  0.750  1.0
  Se  Se15  1  0.427  0.121  0.250  1.0
  O  O16  1  0.274  0.428  0.032  1.0
  O  O17  1  0.274  0.072  0.968  1.0
  O  O18  1  0.726  0.928  0.468  1.0
  O  O19  1  0.726  0.572  0.532  1.0
  O  O20  1  0.726  0.572  0.968  1.0
  O  O21  1  0.726  0.928  0.032  1.0
  O  O22  1  0.274  0.072  0.532  1.0
  O  O23  1  0.274  0.428  0.468  1.0
  O  O24  1  0.049  0.736  0.119  1.0
  O  O25  1  0.049  0.736  0.381  1.0
  O  O26  1  0.951  0.236  0.381  1.0
  O  O27  1  0.951  0.264  0.619  1.0
  O  O28  1  0.951  0.264  0.881  1.0
  O  O29  1  0.951  0.236  0.119  1.0
  O  O30  1  0.049  0.764  0.619  1.0
  O  O31  1  0.049  0.764  0.881  1.0
[/CIF]
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The material structure described by Sm2SiSeO4 crystallizes in the orthorhombic Pbcm space group. There are two inequivalent Sm sites. In the first Sm site, Sm(1) is bonded in a 6-coordinate geometry to two equivalent Se(1), two equivalent O(2), and four equivalent O(1) atoms. In the second Sm site, Sm(2) is bonded in a 8-coordinate geometry to two equivalent Se(1), two equivalent O(1), and four equivalent O(2) atoms. Si(1) is bonded in a tetrahedral geometry to two equivalent O(1) and two equivalent O(2) atoms. Se(1) is bonded in a 4-coordinate geometry to two equivalent Sm(1) and two equivalent Sm(2) atoms. There are two inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Sm(2), two equivalent Sm(1), and one Si(1) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Sm(1), two equivalent Sm(2), and one Si(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sm2SiSeO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.181
_cell_length_b   7.148
_cell_length_c   11.025
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   487.103
_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
  Sm  Sm0  1  0.609  0.250  0.500  1.0
  Sm  Sm1  1  0.609  0.250  0.000  1.0
  Sm  Sm2  1  0.391  0.750  0.500  1.0
  Sm  Sm3  1  0.391  0.750  0.000  1.0
  Sm  Sm4  1  0.868  0.533  0.750  1.0
  Sm  Sm5  1  0.868  0.967  0.250  1.0
  Sm  Sm6  1  0.132  0.033  0.750  1.0
  Sm  Sm7  1  0.132  0.467  0.250  1.0
  Si  Si8  1  0.114  0.250  0.500  1.0
  Si  Si9  1  0.886  0.750  0.500  1.0
  Si  Si10  1  0.886  0.750  0.000  1.0
  Si  Si11  1  0.114  0.250  0.000  1.0
  Se  Se12  1  0.573  0.879  0.750  1.0
  Se  Se13  1  0.573  0.621  0.250  1.0
  Se  Se14  1  0.427  0.379  0.750  1.0
  Se  Se15  1  0.427  0.121  0.250  1.0
  O  O16  1  0.274  0.428  0.032  1.0
  O  O17  1  0.274  0.072  0.968  1.0
  O  O18  1  0.726  0.928  0.468  1.0
  O  O19  1  0.726  0.572  0.532  1.0
  O  O20  1  0.726  0.572  0.968  1.0
  O  O21  1  0.726  0.928  0.032  1.0
  O  O22  1  0.274  0.072  0.532  1.0
  O  O23  1  0.274  0.428  0.468  1.0
  O  O24  1  0.049  0.736  0.119  1.0
  O  O25  1  0.049  0.736  0.381  1.0
  O  O26  1  0.951  0.236  0.381  1.0
  O  O27  1  0.951  0.264  0.619  1.0
  O  O28  1  0.951  0.264  0.881  1.0
  O  O29  1  0.951  0.236  0.119  1.0
  O  O30  1  0.049  0.764  0.619  1.0
  O  O31  1  0.049  0.764  0.881  1.0
[/CIF]
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