The structure described by Mg6YHf crystallizes in the orthorhombic Cmmm space group. There are three inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a distorted body-centered cubic geometry to four equivalent Mg(3), two equivalent Y(1), and two equivalent Hf(1) atoms. In the second Mg site, Mg(2) is bonded in a 8-coordinate geometry to four equivalent Mg(3), two equivalent Y(1), and two equivalent Hf(1) atoms. In the third Mg site, Mg(3) is bonded to four equivalent Mg(1), four equivalent Mg(2), two equivalent Y(1), and two equivalent Hf(1) atoms to form MgY2Hf2Mg8 cuboctahedra that share corners with twelve equivalent Mg(3)Y2Hf2Mg8 cuboctahedra, edges with four equivalent Y(1)Mg12 cuboctahedra, faces with two equivalent Y(1)Mg12 cuboctahedra, and faces with six equivalent Mg(3)Y2Hf2Mg8 cuboctahedra. Y(1) is bonded to four equivalent Mg(1), four equivalent Mg(2), and four equivalent Mg(3) atoms to form distorted YMg12 cuboctahedra that share corners with four equivalent Y(1)Mg12 cuboctahedra, edges with eight equivalent Mg(3)Y2Hf2Mg8 cuboctahedra, faces with two equivalent Y(1)Mg12 cuboctahedra, and faces with four equivalent Mg(3)Y2Hf2Mg8 cuboctahedra. Hf(1) is bonded in a 8-coordinate geometry to four equivalent Mg(1), four equivalent Mg(2), and four equivalent Mg(3) atoms. is represented by the CIF card [CIF]
data_YHfMg6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.261
_cell_length_b   6.261
_cell_length_c   4.890
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   102.849
_symmetry_Int_Tables_number   1
_cell_volume   186.881
_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
  Y  Y0  1  0.500  0.500  0.500  1.0
  Hf  Hf1  1  0.000  0.000  0.500  1.0
  Mg  Mg2  1  0.500  0.000  0.500  1.0
  Mg  Mg3  1  0.000  0.500  0.500  1.0
  Mg  Mg4  1  0.760  0.760  0.000  1.0
  Mg  Mg5  1  0.240  0.240  0.000  1.0
  Mg  Mg6  1  0.755  0.245  0.000  1.0
  Mg  Mg7  1  0.245  0.755  0.000  1.0
[/CIF]
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The structure described by Mg6YHf crystallizes in the orthorhombic Cmmm space group. There are three inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a distorted body-centered cubic geometry to four equivalent Mg(3), two equivalent Y(1), and two equivalent Hf(1) atoms. In the second Mg site, Mg(2) is bonded in a 8-coordinate geometry to four equivalent Mg(3), two equivalent Y(1), and two equivalent Hf(1) atoms. In the third Mg site, Mg(3) is bonded to four equivalent Mg(1), four equivalent Mg(2), two equivalent Y(1), and two equivalent Hf(1) atoms to form MgY2Hf2Mg8 cuboctahedra that share corners with twelve equivalent Mg(3)Y2Hf2Mg8 cuboctahedra, edges with four equivalent Y(1)Mg12 cuboctahedra, faces with two equivalent Y(1)Mg12 cuboctahedra, and faces with six equivalent Mg(3)Y2Hf2Mg8 cuboctahedra. Y(1) is bonded to four equivalent Mg(1), four equivalent Mg(2), and four equivalent Mg(3) atoms to form distorted YMg12 cuboctahedra that share corners with four equivalent Y(1)Mg12 cuboctahedra, edges with eight equivalent Mg(3)Y2Hf2Mg8 cuboctahedra, faces with two equivalent Y(1)Mg12 cuboctahedra, and faces with four equivalent Mg(3)Y2Hf2Mg8 cuboctahedra. Hf(1) is bonded in a 8-coordinate geometry to four equivalent Mg(1), four equivalent Mg(2), and four equivalent Mg(3) atoms. is represented by the CIF card [CIF]
data_YHfMg6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.261
_cell_length_b   6.261
_cell_length_c   4.890
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   102.849
_symmetry_Int_Tables_number   1
_cell_volume   186.881
_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
  Y  Y0  1  0.500  0.500  0.500  1.0
  Hf  Hf1  1  0.000  0.000  0.500  1.0
  Mg  Mg2  1  0.500  0.000  0.500  1.0
  Mg  Mg3  1  0.000  0.500  0.500  1.0
  Mg  Mg4  1  0.760  0.760  0.000  1.0
  Mg  Mg5  1  0.240  0.240  0.000  1.0
  Mg  Mg6  1  0.755  0.245  0.000  1.0
  Mg  Mg7  1  0.245  0.755  0.000  1.0
[/CIF]
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