The material structure described by Mg2SmNi9 crystallizes in the trigonal R-3m space group. Mg(1) is bonded in a 12-coordinate geometry to three equivalent Ni(3) and nine equivalent Ni(2) atoms. Sm(1) is bonded in a distorted hexagonal planar geometry to six equivalent Ni(1) and twelve equivalent Ni(2) atoms. There are three inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a 12-coordinate geometry to three equivalent Sm(1), three equivalent Ni(1), and six equivalent Ni(2) atoms. In the second Ni site, Ni(2) is bonded to three equivalent Mg(1), two equivalent Sm(1), one Ni(3), two equivalent Ni(1), and four equivalent Ni(2) atoms to form NiSm2Mg3Ni7 cuboctahedra that share corners with two equivalent Ni(3)Mg6Ni6 cuboctahedra, corners with fifteen equivalent Ni(2)Sm2Mg3Ni7 cuboctahedra, edges with eight equivalent Ni(2)Sm2Mg3Ni7 cuboctahedra, faces with three equivalent Ni(3)Mg6Ni6 cuboctahedra, and faces with eleven equivalent Ni(2)Sm2Mg3Ni7 cuboctahedra. In the third Ni site, Ni(3) is bonded to six equivalent Mg(1) and six equivalent Ni(2) atoms to form NiMg6Ni6 cuboctahedra that share corners with twelve equivalent Ni(2)Sm2Mg3Ni7 cuboctahedra, edges with six equivalent Ni(3)Mg6Ni6 cuboctahedra, and faces with eighteen equivalent Ni(2)Sm2Mg3Ni7 cuboctahedra. is represented by the CIF file [CIF]
data_SmMg2Ni9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.287
_cell_length_b   8.287
_cell_length_c   8.287
_cell_angle_alpha   33.907
_cell_angle_beta   33.907
_cell_angle_gamma   33.907
_symmetry_Int_Tables_number   1
_cell_volume   157.837
_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  0.000  0.000  0.000  1.0
  Mg  Mg1  1  0.144  0.144  0.144  1.0
  Mg  Mg2  1  0.856  0.856  0.856  1.0
  Ni  Ni3  1  0.334  0.334  0.334  1.0
  Ni  Ni4  1  0.414  0.918  0.414  1.0
  Ni  Ni5  1  0.586  0.586  0.082  1.0
  Ni  Ni6  1  0.918  0.414  0.414  1.0
  Ni  Ni7  1  0.586  0.082  0.586  1.0
  Ni  Ni8  1  0.666  0.666  0.666  1.0
  Ni  Ni9  1  0.500  0.500  0.500  1.0
  Ni  Ni10  1  0.082  0.586  0.586  1.0
  Ni  Ni11  1  0.414  0.414  0.918  1.0
[/CIF]
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The material structure described by Mg2SmNi9 crystallizes in the trigonal R-3m space group. Mg(1) is bonded in a 12-coordinate geometry to three equivalent Ni(3) and nine equivalent Ni(2) atoms. Sm(1) is bonded in a distorted hexagonal planar geometry to six equivalent Ni(1) and twelve equivalent Ni(2) atoms. There are three inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a 12-coordinate geometry to three equivalent Sm(1), three equivalent Ni(1), and six equivalent Ni(2) atoms. In the second Ni site, Ni(2) is bonded to three equivalent Mg(1), two equivalent Sm(1), one Ni(3), two equivalent Ni(1), and four equivalent Ni(2) atoms to form NiSm2Mg3Ni7 cuboctahedra that share corners with two equivalent Ni(3)Mg6Ni6 cuboctahedra, corners with fifteen equivalent Ni(2)Sm2Mg3Ni7 cuboctahedra, edges with eight equivalent Ni(2)Sm2Mg3Ni7 cuboctahedra, faces with three equivalent Ni(3)Mg6Ni6 cuboctahedra, and faces with eleven equivalent Ni(2)Sm2Mg3Ni7 cuboctahedra. In the third Ni site, Ni(3) is bonded to six equivalent Mg(1) and six equivalent Ni(2) atoms to form NiMg6Ni6 cuboctahedra that share corners with twelve equivalent Ni(2)Sm2Mg3Ni7 cuboctahedra, edges with six equivalent Ni(3)Mg6Ni6 cuboctahedra, and faces with eighteen equivalent Ni(2)Sm2Mg3Ni7 cuboctahedra. is represented by the CIF file [CIF]
data_SmMg2Ni9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.287
_cell_length_b   8.287
_cell_length_c   8.287
_cell_angle_alpha   33.907
_cell_angle_beta   33.907
_cell_angle_gamma   33.907
_symmetry_Int_Tables_number   1
_cell_volume   157.837
_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  0.000  0.000  0.000  1.0
  Mg  Mg1  1  0.144  0.144  0.144  1.0
  Mg  Mg2  1  0.856  0.856  0.856  1.0
  Ni  Ni3  1  0.334  0.334  0.334  1.0
  Ni  Ni4  1  0.414  0.918  0.414  1.0
  Ni  Ni5  1  0.586  0.586  0.082  1.0
  Ni  Ni6  1  0.918  0.414  0.414  1.0
  Ni  Ni7  1  0.586  0.082  0.586  1.0
  Ni  Ni8  1  0.666  0.666  0.666  1.0
  Ni  Ni9  1  0.500  0.500  0.500  1.0
  Ni  Ni10  1  0.082  0.586  0.586  1.0
  Ni  Ni11  1  0.414  0.414  0.918  1.0
[/CIF]
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