The compound described by MgNd3 is beta Cu3Ti-like structured and crystallizes in the tetragonal I4/mmm space group. Mg(1) is bonded to four equivalent Nd(1) and eight equivalent Nd(2) atoms to form MgNd12 cuboctahedra that share corners with four equivalent Mg(1)Nd12 cuboctahedra, corners with eight equivalent Nd(1)Nd8Mg4 cuboctahedra, edges with eight equivalent Mg(1)Nd12 cuboctahedra, edges with sixteen equivalent Nd(2)Nd8Mg4 cuboctahedra, faces with four equivalent Mg(1)Nd12 cuboctahedra, faces with six equivalent Nd(1)Nd8Mg4 cuboctahedra, and faces with eight equivalent Nd(2)Nd8Mg4 cuboctahedra. There are two inequivalent Nd sites. In the first Nd site, Nd(1) is bonded to four equivalent Mg(1) and eight equivalent Nd(2) atoms to form NdNd8Mg4 cuboctahedra that share corners with four equivalent Nd(1)Nd8Mg4 cuboctahedra, corners with eight equivalent Mg(1)Nd12 cuboctahedra, edges with eight equivalent Nd(1)Nd8Mg4 cuboctahedra, edges with sixteen equivalent Nd(2)Nd8Mg4 cuboctahedra, faces with four equivalent Nd(1)Nd8Mg4 cuboctahedra, faces with six equivalent Mg(1)Nd12 cuboctahedra, and faces with eight equivalent Nd(2)Nd8Mg4 cuboctahedra. In the second Nd site, Nd(2) is bonded to four equivalent Mg(1), four equivalent Nd(1), and four equivalent Nd(2) atoms to form NdNd8Mg4 cuboctahedra that share corners with twelve equivalent Nd(2)Nd8Mg4 cuboctahedra, edges with eight equivalent Mg(1)Nd12 cuboctahedra, edges with eight equivalent Nd(1)Nd8Mg4 cuboctahedra, edges with eight equivalent Nd(2)Nd8Mg4 cuboctahedra, faces with four equivalent Mg(1)Nd12 cuboctahedra, faces with four equivalent Nd(1)Nd8Mg4 cuboctahedra, and faces with ten equivalent Nd(2)Nd8Mg4 cuboctahedra. is represented by the CIF file [CIF]
data_Nd3Mg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.191
_cell_length_b   6.191
_cell_length_c   6.191
_cell_angle_alpha   132.327
_cell_angle_beta   132.327
_cell_angle_gamma   69.713
_symmetry_Int_Tables_number   1
_cell_volume   127.231
_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  0.500  0.500  0.000  1.0
  Nd  Nd1  1  0.750  0.250  0.500  1.0
  Nd  Nd2  1  0.250  0.750  0.500  1.0
  Mg  Mg3  1  0.000  0.000  0.000  1.0
[/CIF]
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The compound described by MgNd3 is beta Cu3Ti-like structured and crystallizes in the tetragonal I4/mmm space group. Mg(1) is bonded to four equivalent Nd(1) and eight equivalent Nd(2) atoms to form MgNd12 cuboctahedra that share corners with four equivalent Mg(1)Nd12 cuboctahedra, corners with eight equivalent Nd(1)Nd8Mg4 cuboctahedra, edges with eight equivalent Mg(1)Nd12 cuboctahedra, edges with sixteen equivalent Nd(2)Nd8Mg4 cuboctahedra, faces with four equivalent Mg(1)Nd12 cuboctahedra, faces with six equivalent Nd(1)Nd8Mg4 cuboctahedra, and faces with eight equivalent Nd(2)Nd8Mg4 cuboctahedra. There are two inequivalent Nd sites. In the first Nd site, Nd(1) is bonded to four equivalent Mg(1) and eight equivalent Nd(2) atoms to form NdNd8Mg4 cuboctahedra that share corners with four equivalent Nd(1)Nd8Mg4 cuboctahedra, corners with eight equivalent Mg(1)Nd12 cuboctahedra, edges with eight equivalent Nd(1)Nd8Mg4 cuboctahedra, edges with sixteen equivalent Nd(2)Nd8Mg4 cuboctahedra, faces with four equivalent Nd(1)Nd8Mg4 cuboctahedra, faces with six equivalent Mg(1)Nd12 cuboctahedra, and faces with eight equivalent Nd(2)Nd8Mg4 cuboctahedra. In the second Nd site, Nd(2) is bonded to four equivalent Mg(1), four equivalent Nd(1), and four equivalent Nd(2) atoms to form NdNd8Mg4 cuboctahedra that share corners with twelve equivalent Nd(2)Nd8Mg4 cuboctahedra, edges with eight equivalent Mg(1)Nd12 cuboctahedra, edges with eight equivalent Nd(1)Nd8Mg4 cuboctahedra, edges with eight equivalent Nd(2)Nd8Mg4 cuboctahedra, faces with four equivalent Mg(1)Nd12 cuboctahedra, faces with four equivalent Nd(1)Nd8Mg4 cuboctahedra, and faces with ten equivalent Nd(2)Nd8Mg4 cuboctahedra. is represented by the CIF file [CIF]
data_Nd3Mg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.191
_cell_length_b   6.191
_cell_length_c   6.191
_cell_angle_alpha   132.327
_cell_angle_beta   132.327
_cell_angle_gamma   69.713
_symmetry_Int_Tables_number   1
_cell_volume   127.231
_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  0.500  0.500  0.000  1.0
  Nd  Nd1  1  0.750  0.250  0.500  1.0
  Nd  Nd2  1  0.250  0.750  0.500  1.0
  Mg  Mg3  1  0.000  0.000  0.000  1.0
[/CIF]
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