The material described by Mg23Nd6C crystallizes in the cubic Fm-3m space group. There are four inequivalent Mg sites. In the first Mg site, Mg(2) is bonded in a 13-coordinate geometry to one Mg(4), three equivalent Mg(1), three equivalent Mg(2), three equivalent Mg(3), and three equivalent Nd(1) atoms. In the second Mg site, Mg(3) is bonded to four equivalent Mg(1), four equivalent Mg(2), and four equivalent Nd(1) atoms to form MgNd4Mg8 cuboctahedra that share corners with four equivalent Mg(3)Nd4Mg8 cuboctahedra, corners with eight equivalent Mg(1)Nd3Mg9 cuboctahedra, edges with two equivalent C(1)Nd6 octahedra, faces with eight equivalent Mg(1)Nd3Mg9 cuboctahedra, and faces with eight equivalent Mg(3)Nd4Mg8 cuboctahedra. In the third Mg site, Mg(4) is bonded in a body-centered cubic geometry to eight equivalent Mg(2) atoms. In the fourth Mg site, Mg(1) is bonded to three equivalent Mg(1), three equivalent Mg(2), three equivalent Mg(3), and three equivalent Nd(1) atoms to form MgNd3Mg9 cuboctahedra that share corners with six equivalent Mg(1)Nd3Mg9 cuboctahedra, corners with six equivalent Mg(3)Nd4Mg8 cuboctahedra, faces with six equivalent Mg(1)Nd3Mg9 cuboctahedra, faces with six equivalent Mg(3)Nd4Mg8 cuboctahedra, and  a faceface with one C(1)Nd6 octahedra. Nd(1) is bonded in a single-bond geometry to four equivalent Mg(1), four equivalent Mg(2), four equivalent Mg(3), and one C(1) atom. C(1) is bonded to six equivalent Nd(1) atoms to form CNd6 octahedra that share edges with twelve equivalent Mg(3)Nd4Mg8 cuboctahedra and faces with eight equivalent Mg(1)Nd3Mg9 cuboctahedra. is represented by the CIF file [CIF]
data_Nd6Mg23C
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.156
_cell_length_b   10.156
_cell_length_c   10.156
_cell_angle_alpha   60.000
_cell_angle_beta   60.000
_cell_angle_gamma   60.000
_symmetry_Int_Tables_number   1
_cell_volume   740.782
_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
  Nd  Nd0  1  0.816  0.816  0.184  1.0
  Nd  Nd1  1  0.184  0.816  0.184  1.0
  Nd  Nd2  1  0.816  0.184  0.184  1.0
  Nd  Nd3  1  0.184  0.184  0.816  1.0
  Nd  Nd4  1  0.816  0.184  0.816  1.0
  Nd  Nd5  1  0.184  0.816  0.816  1.0
  Mg  Mg6  1  0.829  0.829  0.514  1.0
  Mg  Mg7  1  0.829  0.514  0.829  1.0
  Mg  Mg8  1  0.514  0.829  0.829  1.0
  Mg  Mg9  1  0.829  0.829  0.829  1.0
  Mg  Mg10  1  0.171  0.171  0.486  1.0
  Mg  Mg11  1  0.171  0.486  0.171  1.0
  Mg  Mg12  1  0.486  0.171  0.171  1.0
  Mg  Mg13  1  0.171  0.171  0.171  1.0
  Mg  Mg14  1  0.620  0.620  0.139  1.0
  Mg  Mg15  1  0.620  0.139  0.620  1.0
  Mg  Mg16  1  0.139  0.620  0.620  1.0
  Mg  Mg17  1  0.620  0.620  0.620  1.0
  Mg  Mg18  1  0.380  0.380  0.861  1.0
  Mg  Mg19  1  0.380  0.861  0.380  1.0
  Mg  Mg20  1  0.861  0.380  0.380  1.0
  Mg  Mg21  1  0.380  0.380  0.380  1.0
  Mg  Mg22  1  0.000  0.000  0.500  1.0
  Mg  Mg23  1  0.500  0.000  0.500  1.0
  Mg  Mg24  1  0.000  0.500  0.500  1.0
  Mg  Mg25  1  0.500  0.500  0.000  1.0
  Mg  Mg26  1  0.000  0.500  0.000  1.0
  Mg  Mg27  1  0.500  0.000  0.000  1.0
  Mg  Mg28  1  0.500  0.500  0.500  1.0
  C  C29  1  0.000  0.000  0.000  1.0
[/CIF]
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The material described by Mg23Nd6C crystallizes in the cubic Fm-3m space group. There are four inequivalent Mg sites. In the first Mg site, Mg(2) is bonded in a 13-coordinate geometry to one Mg(4), three equivalent Mg(1), three equivalent Mg(2), three equivalent Mg(3), and three equivalent Nd(1) atoms. In the second Mg site, Mg(3) is bonded to four equivalent Mg(1), four equivalent Mg(2), and four equivalent Nd(1) atoms to form MgNd4Mg8 cuboctahedra that share corners with four equivalent Mg(3)Nd4Mg8 cuboctahedra, corners with eight equivalent Mg(1)Nd3Mg9 cuboctahedra, edges with two equivalent C(1)Nd6 octahedra, faces with eight equivalent Mg(1)Nd3Mg9 cuboctahedra, and faces with eight equivalent Mg(3)Nd4Mg8 cuboctahedra. In the third Mg site, Mg(4) is bonded in a body-centered cubic geometry to eight equivalent Mg(2) atoms. In the fourth Mg site, Mg(1) is bonded to three equivalent Mg(1), three equivalent Mg(2), three equivalent Mg(3), and three equivalent Nd(1) atoms to form MgNd3Mg9 cuboctahedra that share corners with six equivalent Mg(1)Nd3Mg9 cuboctahedra, corners with six equivalent Mg(3)Nd4Mg8 cuboctahedra, faces with six equivalent Mg(1)Nd3Mg9 cuboctahedra, faces with six equivalent Mg(3)Nd4Mg8 cuboctahedra, and  a faceface with one C(1)Nd6 octahedra. Nd(1) is bonded in a single-bond geometry to four equivalent Mg(1), four equivalent Mg(2), four equivalent Mg(3), and one C(1) atom. C(1) is bonded to six equivalent Nd(1) atoms to form CNd6 octahedra that share edges with twelve equivalent Mg(3)Nd4Mg8 cuboctahedra and faces with eight equivalent Mg(1)Nd3Mg9 cuboctahedra. is represented by the CIF file [CIF]
data_Nd6Mg23C
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.156
_cell_length_b   10.156
_cell_length_c   10.156
_cell_angle_alpha   60.000
_cell_angle_beta   60.000
_cell_angle_gamma   60.000
_symmetry_Int_Tables_number   1
_cell_volume   740.782
_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
  Nd  Nd0  1  0.816  0.816  0.184  1.0
  Nd  Nd1  1  0.184  0.816  0.184  1.0
  Nd  Nd2  1  0.816  0.184  0.184  1.0
  Nd  Nd3  1  0.184  0.184  0.816  1.0
  Nd  Nd4  1  0.816  0.184  0.816  1.0
  Nd  Nd5  1  0.184  0.816  0.816  1.0
  Mg  Mg6  1  0.829  0.829  0.514  1.0
  Mg  Mg7  1  0.829  0.514  0.829  1.0
  Mg  Mg8  1  0.514  0.829  0.829  1.0
  Mg  Mg9  1  0.829  0.829  0.829  1.0
  Mg  Mg10  1  0.171  0.171  0.486  1.0
  Mg  Mg11  1  0.171  0.486  0.171  1.0
  Mg  Mg12  1  0.486  0.171  0.171  1.0
  Mg  Mg13  1  0.171  0.171  0.171  1.0
  Mg  Mg14  1  0.620  0.620  0.139  1.0
  Mg  Mg15  1  0.620  0.139  0.620  1.0
  Mg  Mg16  1  0.139  0.620  0.620  1.0
  Mg  Mg17  1  0.620  0.620  0.620  1.0
  Mg  Mg18  1  0.380  0.380  0.861  1.0
  Mg  Mg19  1  0.380  0.861  0.380  1.0
  Mg  Mg20  1  0.861  0.380  0.380  1.0
  Mg  Mg21  1  0.380  0.380  0.380  1.0
  Mg  Mg22  1  0.000  0.000  0.500  1.0
  Mg  Mg23  1  0.500  0.000  0.500  1.0
  Mg  Mg24  1  0.000  0.500  0.500  1.0
  Mg  Mg25  1  0.500  0.500  0.000  1.0
  Mg  Mg26  1  0.000  0.500  0.000  1.0
  Mg  Mg27  1  0.500  0.000  0.000  1.0
  Mg  Mg28  1  0.500  0.500  0.500  1.0
  C  C29  1  0.000  0.000  0.000  1.0
[/CIF]
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