The crystal structure described by Sm5Si2B8 crystallizes in the tetragonal P4/mbm space group. There are two inequivalent Sm sites. In the first Sm site, Sm(1) is bonded in a 12-coordinate geometry to two equivalent B(3), three equivalent B(2), four equivalent B(1), and three equivalent Si(1) atoms. In the second Sm site, Sm(2) is bonded to two equivalent B(3) and four equivalent Si(1) atoms to form corner-sharing SmSi4B2 octahedra. The corner-sharing octahedral tilt angles are 57°. There are three inequivalent B sites. In the first B site, B(1) is bonded in a 9-coordinate geometry to four equivalent Sm(1), one B(2), two equivalent B(1), and two equivalent B(3) atoms. In the second B site, B(2) is bonded in a 9-coordinate geometry to six equivalent Sm(1), one B(2), and two equivalent B(1) atoms. In the third B site, B(3) is bonded in a 9-coordinate geometry to one Sm(2), four equivalent Sm(1), and four equivalent B(1) atoms. Si(1) is bonded in a 9-coordinate geometry to two equivalent Sm(2), six equivalent Sm(1), and one Si(1) atom. is represented by the CIF card [CIF]
data_Sm5(SiB4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.355
_cell_length_b   7.355
_cell_length_c   8.365
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   452.484
_cell_formula_units_Z   2
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  0.680  0.180  0.224  1.0
  Sm  Sm1  1  0.320  0.820  0.776  1.0
  Sm  Sm2  1  0.320  0.820  0.224  1.0
  Sm  Sm3  1  0.820  0.680  0.224  1.0
  Sm  Sm4  1  0.820  0.680  0.776  1.0
  Sm  Sm5  1  0.680  0.180  0.776  1.0
  Sm  Sm6  1  0.180  0.320  0.776  1.0
  Sm  Sm7  1  0.180  0.320  0.224  1.0
  Sm  Sm8  1  0.000  0.000  0.500  1.0
  Sm  Sm9  1  0.500  0.500  0.500  1.0
  Si  Si10  1  0.113  0.613  0.500  1.0
  Si  Si11  1  0.887  0.387  0.500  1.0
  Si  Si12  1  0.387  0.113  0.500  1.0
  Si  Si13  1  0.613  0.887  0.500  1.0
  B  B14  1  0.171  0.039  0.000  1.0
  B  B15  1  0.829  0.961  0.000  1.0
  B  B16  1  0.961  0.171  0.000  1.0
  B  B17  1  0.329  0.539  0.000  1.0
  B  B18  1  0.039  0.829  0.000  1.0
  B  B19  1  0.671  0.461  0.000  1.0
  B  B20  1  0.539  0.671  0.000  1.0
  B  B21  1  0.461  0.329  0.000  1.0
  B  B22  1  0.091  0.591  0.000  1.0
  B  B23  1  0.909  0.409  0.000  1.0
  B  B24  1  0.409  0.091  0.000  1.0
  B  B25  1  0.591  0.909  0.000  1.0
  B  B26  1  0.000  0.000  0.156  1.0
  B  B27  1  0.000  0.000  0.844  1.0
  B  B28  1  0.500  0.500  0.844  1.0
  B  B29  1  0.500  0.500  0.156  1.0
[/CIF]
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The crystal structure described by Sm5Si2B8 crystallizes in the tetragonal P4/mbm space group. There are two inequivalent Sm sites. In the first Sm site, Sm(1) is bonded in a 12-coordinate geometry to two equivalent B(3), three equivalent B(2), four equivalent B(1), and three equivalent Si(1) atoms. In the second Sm site, Sm(2) is bonded to two equivalent B(3) and four equivalent Si(1) atoms to form corner-sharing SmSi4B2 octahedra. The corner-sharing octahedral tilt angles are 57°. There are three inequivalent B sites. In the first B site, B(1) is bonded in a 9-coordinate geometry to four equivalent Sm(1), one B(2), two equivalent B(1), and two equivalent B(3) atoms. In the second B site, B(2) is bonded in a 9-coordinate geometry to six equivalent Sm(1), one B(2), and two equivalent B(1) atoms. In the third B site, B(3) is bonded in a 9-coordinate geometry to one Sm(2), four equivalent Sm(1), and four equivalent B(1) atoms. Si(1) is bonded in a 9-coordinate geometry to two equivalent Sm(2), six equivalent Sm(1), and one Si(1) atom. is represented by the CIF card [CIF]
data_Sm5(SiB4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.355
_cell_length_b   7.355
_cell_length_c   8.365
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   452.484
_cell_formula_units_Z   2
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  0.680  0.180  0.224  1.0
  Sm  Sm1  1  0.320  0.820  0.776  1.0
  Sm  Sm2  1  0.320  0.820  0.224  1.0
  Sm  Sm3  1  0.820  0.680  0.224  1.0
  Sm  Sm4  1  0.820  0.680  0.776  1.0
  Sm  Sm5  1  0.680  0.180  0.776  1.0
  Sm  Sm6  1  0.180  0.320  0.776  1.0
  Sm  Sm7  1  0.180  0.320  0.224  1.0
  Sm  Sm8  1  0.000  0.000  0.500  1.0
  Sm  Sm9  1  0.500  0.500  0.500  1.0
  Si  Si10  1  0.113  0.613  0.500  1.0
  Si  Si11  1  0.887  0.387  0.500  1.0
  Si  Si12  1  0.387  0.113  0.500  1.0
  Si  Si13  1  0.613  0.887  0.500  1.0
  B  B14  1  0.171  0.039  0.000  1.0
  B  B15  1  0.829  0.961  0.000  1.0
  B  B16  1  0.961  0.171  0.000  1.0
  B  B17  1  0.329  0.539  0.000  1.0
  B  B18  1  0.039  0.829  0.000  1.0
  B  B19  1  0.671  0.461  0.000  1.0
  B  B20  1  0.539  0.671  0.000  1.0
  B  B21  1  0.461  0.329  0.000  1.0
  B  B22  1  0.091  0.591  0.000  1.0
  B  B23  1  0.909  0.409  0.000  1.0
  B  B24  1  0.409  0.091  0.000  1.0
  B  B25  1  0.591  0.909  0.000  1.0
  B  B26  1  0.000  0.000  0.156  1.0
  B  B27  1  0.000  0.000  0.844  1.0
  B  B28  1  0.500  0.500  0.844  1.0
  B  B29  1  0.500  0.500  0.156  1.0
[/CIF]
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