The compound described by Sm3NiSi3 crystallizes in the orthorhombic Imm2 space group. There are three inequivalent Sm sites. In the first Sm site, Sm(1) is bonded in a 7-coordinate geometry to one Si(1), two equivalent Si(3), and four equivalent Si(2) atoms. In the second Sm site, Sm(2) is bonded in a 7-coordinate geometry to two equivalent Ni(1), one Si(2), and four equivalent Si(1) atoms. In the third Sm site, Sm(3) is bonded to four equivalent Ni(1), two equivalent Si(1), two equivalent Si(2), and four equivalent Si(3) atoms to form a mixture of face and edge-sharing SmSi8Ni4 cuboctahedra. Ni(1) is bonded in a 9-coordinate geometry to two equivalent Sm(2), four equivalent Sm(3), one Si(3), and two equivalent Si(1) atoms. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to one Sm(1), two equivalent Sm(3), four equivalent Sm(2), and two equivalent Ni(1) atoms. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to one Sm(2), two equivalent Sm(3), four equivalent Sm(1), and two equivalent Si(3) atoms. In the third Si site, Si(3) is bonded in a 9-coordinate geometry to two equivalent Sm(1), four equivalent Sm(3), one Ni(1), and two equivalent Si(2) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sm3Si3Ni
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.374
_cell_length_b   9.374
_cell_length_c   9.374
_cell_angle_alpha   155.465
_cell_angle_beta   153.825
_cell_angle_gamma   36.181
_symmetry_Int_Tables_number   1
_cell_volume   150.698
_cell_formula_units_Z   1
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  0.815  0.315  0.500  1.0
  Sm  Sm1  1  0.182  0.682  0.500  1.0
  Sm  Sm2  1  0.001  0.001  0.000  1.0
  Si  Si3  1  0.636  0.136  0.500  1.0
  Si  Si4  1  0.359  0.859  0.500  1.0
  Si  Si5  1  0.441  0.441  0.000  1.0
  Ni  Ni6  1  0.567  0.567  0.000  1.0
[/CIF]
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The compound described by Sm3NiSi3 crystallizes in the orthorhombic Imm2 space group. There are three inequivalent Sm sites. In the first Sm site, Sm(1) is bonded in a 7-coordinate geometry to one Si(1), two equivalent Si(3), and four equivalent Si(2) atoms. In the second Sm site, Sm(2) is bonded in a 7-coordinate geometry to two equivalent Ni(1), one Si(2), and four equivalent Si(1) atoms. In the third Sm site, Sm(3) is bonded to four equivalent Ni(1), two equivalent Si(1), two equivalent Si(2), and four equivalent Si(3) atoms to form a mixture of face and edge-sharing SmSi8Ni4 cuboctahedra. Ni(1) is bonded in a 9-coordinate geometry to two equivalent Sm(2), four equivalent Sm(3), one Si(3), and two equivalent Si(1) atoms. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to one Sm(1), two equivalent Sm(3), four equivalent Sm(2), and two equivalent Ni(1) atoms. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to one Sm(2), two equivalent Sm(3), four equivalent Sm(1), and two equivalent Si(3) atoms. In the third Si site, Si(3) is bonded in a 9-coordinate geometry to two equivalent Sm(1), four equivalent Sm(3), one Ni(1), and two equivalent Si(2) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sm3Si3Ni
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.374
_cell_length_b   9.374
_cell_length_c   9.374
_cell_angle_alpha   155.465
_cell_angle_beta   153.825
_cell_angle_gamma   36.181
_symmetry_Int_Tables_number   1
_cell_volume   150.698
_cell_formula_units_Z   1
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  0.815  0.315  0.500  1.0
  Sm  Sm1  1  0.182  0.682  0.500  1.0
  Sm  Sm2  1  0.001  0.001  0.000  1.0
  Si  Si3  1  0.636  0.136  0.500  1.0
  Si  Si4  1  0.359  0.859  0.500  1.0
  Si  Si5  1  0.441  0.441  0.000  1.0
  Ni  Ni6  1  0.567  0.567  0.000  1.0
[/CIF]
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