The compound described by Mg6FeNi is beta Cu3Ti-derived structured and crystallizes in the hexagonal P-6m2 space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to four equivalent Mg(1), four equivalent Mg(2), two equivalent Fe(1), and two equivalent Ni(1) atoms to form distorted MgMg8Fe2Ni2 cuboctahedra that share corners with four equivalent Fe(1)Mg12 cuboctahedra, corners with fourteen equivalent Mg(1)Mg8Fe2Ni2 cuboctahedra, edges with two equivalent Fe(1)Mg12 cuboctahedra, edges with four equivalent Mg(1)Mg8Fe2Ni2 cuboctahedra, edges with four equivalent Ni(1)Mg12 cuboctahedra, edges with eight equivalent Mg(2)Mg8Fe2Ni2 cuboctahedra, faces with two equivalent Fe(1)Mg12 cuboctahedra, faces with two equivalent Ni(1)Mg12 cuboctahedra, faces with six equivalent Mg(1)Mg8Fe2Ni2 cuboctahedra, and faces with ten equivalent Mg(2)Mg8Fe2Ni2 cuboctahedra. In the second Mg site, Mg(2) is bonded to four equivalent Mg(1), four equivalent Mg(2), two equivalent Fe(1), and two equivalent Ni(1) atoms to form distorted MgMg8Fe2Ni2 cuboctahedra that share corners with four equivalent Ni(1)Mg12 cuboctahedra, corners with fourteen equivalent Mg(2)Mg8Fe2Ni2 cuboctahedra, edges with two equivalent Ni(1)Mg12 cuboctahedra, edges with four equivalent Mg(2)Mg8Fe2Ni2 cuboctahedra, edges with four equivalent Fe(1)Mg12 cuboctahedra, edges with eight equivalent Mg(1)Mg8Fe2Ni2 cuboctahedra, faces with two equivalent Fe(1)Mg12 cuboctahedra, faces with two equivalent Ni(1)Mg12 cuboctahedra, faces with six equivalent Mg(2)Mg8Fe2Ni2 cuboctahedra, and faces with ten equivalent Mg(1)Mg8Fe2Ni2 cuboctahedra. Fe(1) is bonded to six equivalent Mg(1) and six equivalent Mg(2) atoms to form FeMg12 cuboctahedra that share corners with six equivalent Fe(1)Mg12 cuboctahedra, corners with twelve equivalent Mg(1)Mg8Fe2Ni2 cuboctahedra, edges with six equivalent Mg(1)Mg8Fe2Ni2 cuboctahedra, edges with twelve equivalent Mg(2)Mg8Fe2Ni2 cuboctahedra, faces with two equivalent Fe(1)Mg12 cuboctahedra, faces with six equivalent Mg(1)Mg8Fe2Ni2 cuboctahedra, faces with six equivalent Mg(2)Mg8Fe2Ni2 cuboctahedra, and faces with six equivalent Ni(1)Mg12 cuboctahedra. Ni(1) is bonded to six equivalent Mg(1) and six equivalent Mg(2) atoms to form NiMg12 cuboctahedra that share corners with six equivalent Ni(1)Mg12 cuboctahedra, corners with twelve equivalent Mg(2)Mg8Fe2Ni2 cuboctahedra, edges with six equivalent Mg(2)Mg8Fe2Ni2 cuboctahedra, edges with twelve equivalent Mg(1)Mg8Fe2Ni2 cuboctahedra, faces with two equivalent Ni(1)Mg12 cuboctahedra, faces with six equivalent Mg(1)Mg8Fe2Ni2 cuboctahedra, faces with six equivalent Mg(2)Mg8Fe2Ni2 cuboctahedra, and faces with six equivalent Fe(1)Mg12 cuboctahedra. is represented by the CIF card [CIF]
data_Mg6FeNi
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.995
_cell_length_b   5.995
_cell_length_c   4.745
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   147.693
_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
  Mg  Mg0  1  0.827  0.653  0.000  1.0
  Mg  Mg1  1  0.347  0.173  0.000  1.0
  Mg  Mg2  1  0.827  0.173  0.000  1.0
  Mg  Mg3  1  0.174  0.349  0.500  1.0
  Mg  Mg4  1  0.651  0.826  0.500  1.0
  Mg  Mg5  1  0.174  0.826  0.500  1.0
  Fe  Fe6  1  0.333  0.667  0.000  1.0
  Ni  Ni7  1  0.667  0.333  0.500  1.0
[/CIF]
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The compound described by Mg6FeNi is beta Cu3Ti-derived structured and crystallizes in the hexagonal P-6m2 space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to four equivalent Mg(1), four equivalent Mg(2), two equivalent Fe(1), and two equivalent Ni(1) atoms to form distorted MgMg8Fe2Ni2 cuboctahedra that share corners with four equivalent Fe(1)Mg12 cuboctahedra, corners with fourteen equivalent Mg(1)Mg8Fe2Ni2 cuboctahedra, edges with two equivalent Fe(1)Mg12 cuboctahedra, edges with four equivalent Mg(1)Mg8Fe2Ni2 cuboctahedra, edges with four equivalent Ni(1)Mg12 cuboctahedra, edges with eight equivalent Mg(2)Mg8Fe2Ni2 cuboctahedra, faces with two equivalent Fe(1)Mg12 cuboctahedra, faces with two equivalent Ni(1)Mg12 cuboctahedra, faces with six equivalent Mg(1)Mg8Fe2Ni2 cuboctahedra, and faces with ten equivalent Mg(2)Mg8Fe2Ni2 cuboctahedra. In the second Mg site, Mg(2) is bonded to four equivalent Mg(1), four equivalent Mg(2), two equivalent Fe(1), and two equivalent Ni(1) atoms to form distorted MgMg8Fe2Ni2 cuboctahedra that share corners with four equivalent Ni(1)Mg12 cuboctahedra, corners with fourteen equivalent Mg(2)Mg8Fe2Ni2 cuboctahedra, edges with two equivalent Ni(1)Mg12 cuboctahedra, edges with four equivalent Mg(2)Mg8Fe2Ni2 cuboctahedra, edges with four equivalent Fe(1)Mg12 cuboctahedra, edges with eight equivalent Mg(1)Mg8Fe2Ni2 cuboctahedra, faces with two equivalent Fe(1)Mg12 cuboctahedra, faces with two equivalent Ni(1)Mg12 cuboctahedra, faces with six equivalent Mg(2)Mg8Fe2Ni2 cuboctahedra, and faces with ten equivalent Mg(1)Mg8Fe2Ni2 cuboctahedra. Fe(1) is bonded to six equivalent Mg(1) and six equivalent Mg(2) atoms to form FeMg12 cuboctahedra that share corners with six equivalent Fe(1)Mg12 cuboctahedra, corners with twelve equivalent Mg(1)Mg8Fe2Ni2 cuboctahedra, edges with six equivalent Mg(1)Mg8Fe2Ni2 cuboctahedra, edges with twelve equivalent Mg(2)Mg8Fe2Ni2 cuboctahedra, faces with two equivalent Fe(1)Mg12 cuboctahedra, faces with six equivalent Mg(1)Mg8Fe2Ni2 cuboctahedra, faces with six equivalent Mg(2)Mg8Fe2Ni2 cuboctahedra, and faces with six equivalent Ni(1)Mg12 cuboctahedra. Ni(1) is bonded to six equivalent Mg(1) and six equivalent Mg(2) atoms to form NiMg12 cuboctahedra that share corners with six equivalent Ni(1)Mg12 cuboctahedra, corners with twelve equivalent Mg(2)Mg8Fe2Ni2 cuboctahedra, edges with six equivalent Mg(2)Mg8Fe2Ni2 cuboctahedra, edges with twelve equivalent Mg(1)Mg8Fe2Ni2 cuboctahedra, faces with two equivalent Ni(1)Mg12 cuboctahedra, faces with six equivalent Mg(1)Mg8Fe2Ni2 cuboctahedra, faces with six equivalent Mg(2)Mg8Fe2Ni2 cuboctahedra, and faces with six equivalent Fe(1)Mg12 cuboctahedra. is represented by the CIF card [CIF]
data_Mg6FeNi
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.995
_cell_length_b   5.995
_cell_length_c   4.745
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   147.693
_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
  Mg  Mg0  1  0.827  0.653  0.000  1.0
  Mg  Mg1  1  0.347  0.173  0.000  1.0
  Mg  Mg2  1  0.827  0.173  0.000  1.0
  Mg  Mg3  1  0.174  0.349  0.500  1.0
  Mg  Mg4  1  0.651  0.826  0.500  1.0
  Mg  Mg5  1  0.174  0.826  0.500  1.0
  Fe  Fe6  1  0.333  0.667  0.000  1.0
  Ni  Ni7  1  0.667  0.333  0.500  1.0
[/CIF]
.