The material described by Mg3In is Uranium Silicide-like structured and crystallizes in the trigonal R-3m space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent Mg(2), six equivalent Mg(1), one In(2), and three equivalent In(1) atoms to form distorted MgMg8In4 cuboctahedra that share corners with two equivalent In(2)Mg12 cuboctahedra, corners with six equivalent Mg(1)Mg8In4 cuboctahedra, corners with seven equivalent Mg(2)Mg8In4 cuboctahedra, edges with three equivalent In(2)Mg12 cuboctahedra, edges with four equivalent In(1)Mg12 cuboctahedra, edges with six equivalent Mg(2)Mg8In4 cuboctahedra, edges with eight equivalent Mg(1)Mg8In4 cuboctahedra,  a faceface with one In(2)Mg12 cuboctahedra, faces with three equivalent In(1)Mg12 cuboctahedra, faces with six equivalent Mg(2)Mg8In4 cuboctahedra, and faces with nine equivalent Mg(1)Mg8In4 cuboctahedra. In the second Mg site, Mg(2) is bonded to two equivalent Mg(1), six equivalent Mg(2), one In(1), and three equivalent In(2) atoms to form distorted MgMg8In4 cuboctahedra that share corners with two equivalent In(1)Mg12 cuboctahedra, corners with six equivalent Mg(2)Mg8In4 cuboctahedra, corners with seven equivalent Mg(1)Mg8In4 cuboctahedra, edges with three equivalent In(1)Mg12 cuboctahedra, edges with four equivalent In(2)Mg12 cuboctahedra, edges with six equivalent Mg(1)Mg8In4 cuboctahedra, edges with eight equivalent Mg(2)Mg8In4 cuboctahedra,  a faceface with one In(1)Mg12 cuboctahedra, faces with three equivalent In(2)Mg12 cuboctahedra, faces with six equivalent Mg(1)Mg8In4 cuboctahedra, and faces with nine equivalent Mg(2)Mg8In4 cuboctahedra. There are two inequivalent In sites. In the first In site, In(1) is bonded to three equivalent Mg(2) and nine equivalent Mg(1) atoms to form InMg12 cuboctahedra that share corners with three equivalent In(2)Mg12 cuboctahedra, corners with six equivalent Mg(2)Mg8In4 cuboctahedra, corners with six equivalent In(1)Mg12 cuboctahedra, edges with nine equivalent Mg(2)Mg8In4 cuboctahedra, edges with twelve equivalent Mg(1)Mg8In4 cuboctahedra, faces with three equivalent Mg(2)Mg8In4 cuboctahedra, faces with three equivalent In(1)Mg12 cuboctahedra, faces with four equivalent In(2)Mg12 cuboctahedra, and faces with nine equivalent Mg(1)Mg8In4 cuboctahedra. In the second In site, In(2) is bonded to three equivalent Mg(1) and nine equivalent Mg(2) atoms to form InMg12 cuboctahedra that share corners with three equivalent In(1)Mg12 cuboctahedra, corners with six equivalent Mg(1)Mg8In4 cuboctahedra, corners with six equivalent In(2)Mg12 cuboctahedra, edges with nine equivalent Mg(1)Mg8In4 cuboctahedra, edges with twelve equivalent Mg(2)Mg8In4 cuboctahedra, faces with three equivalent Mg(1)Mg8In4 cuboctahedra, faces with three equivalent In(2)Mg12 cuboctahedra, faces with four equivalent In(1)Mg12 cuboctahedra, and faces with nine equivalent Mg(2)Mg8In4 cuboctahedra. is represented by the CIF file [CIF]
data_Mg3In
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.972
_cell_length_b   10.972
_cell_length_c   10.972
_cell_angle_alpha   33.280
_cell_angle_beta   33.280
_cell_angle_gamma   33.280
_symmetry_Int_Tables_number   1
_cell_volume   354.115
_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
  Mg  Mg0  1  0.001  0.499  0.499  1.0
  Mg  Mg1  1  0.499  0.499  0.001  1.0
  Mg  Mg2  1  0.499  0.001  0.499  1.0
  Mg  Mg3  1  0.417  0.917  0.917  1.0
  Mg  Mg4  1  0.917  0.917  0.417  1.0
  Mg  Mg5  1  0.917  0.417  0.917  1.0
  Mg  Mg6  1  0.833  0.333  0.333  1.0
  Mg  Mg7  1  0.333  0.333  0.833  1.0
  Mg  Mg8  1  0.333  0.833  0.333  1.0
  Mg  Mg9  1  0.249  0.751  0.751  1.0
  Mg  Mg10  1  0.751  0.751  0.249  1.0
  Mg  Mg11  1  0.751  0.249  0.751  1.0
  In  In12  1  1.000  1.000  1.000  1.0
  In  In13  1  0.250  0.250  0.250  1.0
  In  In14  1  0.416  0.416  0.416  1.0
  In  In15  1  0.834  0.834  0.834  1.0
[/CIF]
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The material described by Mg3In is Uranium Silicide-like structured and crystallizes in the trigonal R-3m space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent Mg(2), six equivalent Mg(1), one In(2), and three equivalent In(1) atoms to form distorted MgMg8In4 cuboctahedra that share corners with two equivalent In(2)Mg12 cuboctahedra, corners with six equivalent Mg(1)Mg8In4 cuboctahedra, corners with seven equivalent Mg(2)Mg8In4 cuboctahedra, edges with three equivalent In(2)Mg12 cuboctahedra, edges with four equivalent In(1)Mg12 cuboctahedra, edges with six equivalent Mg(2)Mg8In4 cuboctahedra, edges with eight equivalent Mg(1)Mg8In4 cuboctahedra,  a faceface with one In(2)Mg12 cuboctahedra, faces with three equivalent In(1)Mg12 cuboctahedra, faces with six equivalent Mg(2)Mg8In4 cuboctahedra, and faces with nine equivalent Mg(1)Mg8In4 cuboctahedra. In the second Mg site, Mg(2) is bonded to two equivalent Mg(1), six equivalent Mg(2), one In(1), and three equivalent In(2) atoms to form distorted MgMg8In4 cuboctahedra that share corners with two equivalent In(1)Mg12 cuboctahedra, corners with six equivalent Mg(2)Mg8In4 cuboctahedra, corners with seven equivalent Mg(1)Mg8In4 cuboctahedra, edges with three equivalent In(1)Mg12 cuboctahedra, edges with four equivalent In(2)Mg12 cuboctahedra, edges with six equivalent Mg(1)Mg8In4 cuboctahedra, edges with eight equivalent Mg(2)Mg8In4 cuboctahedra,  a faceface with one In(1)Mg12 cuboctahedra, faces with three equivalent In(2)Mg12 cuboctahedra, faces with six equivalent Mg(1)Mg8In4 cuboctahedra, and faces with nine equivalent Mg(2)Mg8In4 cuboctahedra. There are two inequivalent In sites. In the first In site, In(1) is bonded to three equivalent Mg(2) and nine equivalent Mg(1) atoms to form InMg12 cuboctahedra that share corners with three equivalent In(2)Mg12 cuboctahedra, corners with six equivalent Mg(2)Mg8In4 cuboctahedra, corners with six equivalent In(1)Mg12 cuboctahedra, edges with nine equivalent Mg(2)Mg8In4 cuboctahedra, edges with twelve equivalent Mg(1)Mg8In4 cuboctahedra, faces with three equivalent Mg(2)Mg8In4 cuboctahedra, faces with three equivalent In(1)Mg12 cuboctahedra, faces with four equivalent In(2)Mg12 cuboctahedra, and faces with nine equivalent Mg(1)Mg8In4 cuboctahedra. In the second In site, In(2) is bonded to three equivalent Mg(1) and nine equivalent Mg(2) atoms to form InMg12 cuboctahedra that share corners with three equivalent In(1)Mg12 cuboctahedra, corners with six equivalent Mg(1)Mg8In4 cuboctahedra, corners with six equivalent In(2)Mg12 cuboctahedra, edges with nine equivalent Mg(1)Mg8In4 cuboctahedra, edges with twelve equivalent Mg(2)Mg8In4 cuboctahedra, faces with three equivalent Mg(1)Mg8In4 cuboctahedra, faces with three equivalent In(2)Mg12 cuboctahedra, faces with four equivalent In(1)Mg12 cuboctahedra, and faces with nine equivalent Mg(2)Mg8In4 cuboctahedra. is represented by the CIF file [CIF]
data_Mg3In
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.972
_cell_length_b   10.972
_cell_length_c   10.972
_cell_angle_alpha   33.280
_cell_angle_beta   33.280
_cell_angle_gamma   33.280
_symmetry_Int_Tables_number   1
_cell_volume   354.115
_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
  Mg  Mg0  1  0.001  0.499  0.499  1.0
  Mg  Mg1  1  0.499  0.499  0.001  1.0
  Mg  Mg2  1  0.499  0.001  0.499  1.0
  Mg  Mg3  1  0.417  0.917  0.917  1.0
  Mg  Mg4  1  0.917  0.917  0.417  1.0
  Mg  Mg5  1  0.917  0.417  0.917  1.0
  Mg  Mg6  1  0.833  0.333  0.333  1.0
  Mg  Mg7  1  0.333  0.333  0.833  1.0
  Mg  Mg8  1  0.333  0.833  0.333  1.0
  Mg  Mg9  1  0.249  0.751  0.751  1.0
  Mg  Mg10  1  0.751  0.751  0.249  1.0
  Mg  Mg11  1  0.751  0.249  0.751  1.0
  In  In12  1  1.000  1.000  1.000  1.0
  In  In13  1  0.250  0.250  0.250  1.0
  In  In14  1  0.416  0.416  0.416  1.0
  In  In15  1  0.834  0.834  0.834  1.0
[/CIF]
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