The material described by Mg6HfCu crystallizes in the orthorhombic Amm2 space group. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a distorted single-bond geometry to two equivalent Mg(4), two equivalent Hf(1), and one Cu(1) atom. In the second Mg site, Mg(2) is bonded in a 2-coordinate geometry to two equivalent Mg(4), two equivalent Hf(1), and two equivalent Cu(1) atoms. In the third Mg site, Mg(3) is bonded in a 2-coordinate geometry to two equivalent Mg(4) and two equivalent Cu(1) atoms. In the fourth Mg site, Mg(4) is bonded to two equivalent Mg(3), four equivalent Mg(1), four equivalent Mg(2), and two equivalent Hf(1) atoms to form MgHf2Mg10 cuboctahedra that share corners with six equivalent Mg(4)Hf2Mg10 cuboctahedra, edges with four equivalent Hf(1)Mg10Cu2 cuboctahedra, faces with two equivalent Mg(4)Hf2Mg10 cuboctahedra, and faces with two equivalent Hf(1)Mg10Cu2 cuboctahedra. Hf(1) is bonded to two equivalent Mg(4), four equivalent Mg(1), four equivalent Mg(2), and two equivalent Cu(1) atoms to form distorted HfMg10Cu2 cuboctahedra that share corners with six equivalent Hf(1)Mg10Cu2 cuboctahedra, edges with four equivalent Mg(4)Hf2Mg10 cuboctahedra, faces with two equivalent Mg(4)Hf2Mg10 cuboctahedra, and faces with two equivalent Hf(1)Mg10Cu2 cuboctahedra. Cu(1) is bonded in a 10-coordinate geometry to two equivalent Mg(1), two equivalent Mg(3), four equivalent Mg(2), and two equivalent Hf(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_HfMg6Cu
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.906
_cell_length_b   5.938
_cell_length_c   6.414
_cell_angle_alpha   117.577
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   165.638
_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
  Cu  Cu0  1  0.500  0.152  0.305  1.0
  Hf  Hf1  1  0.500  0.682  0.363  1.0
  Mg  Mg2  1  0.500  0.681  0.859  1.0
  Mg  Mg3  1  0.500  0.178  0.859  1.0
  Mg  Mg4  1  0.000  0.831  0.164  1.0
  Mg  Mg5  1  1.000  0.333  0.164  1.0
  Mg  Mg6  1  0.000  0.310  0.620  1.0
  Mg  Mg7  1  0.000  0.833  0.667  1.0
[/CIF]
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The material described by Mg6HfCu crystallizes in the orthorhombic Amm2 space group. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a distorted single-bond geometry to two equivalent Mg(4), two equivalent Hf(1), and one Cu(1) atom. In the second Mg site, Mg(2) is bonded in a 2-coordinate geometry to two equivalent Mg(4), two equivalent Hf(1), and two equivalent Cu(1) atoms. In the third Mg site, Mg(3) is bonded in a 2-coordinate geometry to two equivalent Mg(4) and two equivalent Cu(1) atoms. In the fourth Mg site, Mg(4) is bonded to two equivalent Mg(3), four equivalent Mg(1), four equivalent Mg(2), and two equivalent Hf(1) atoms to form MgHf2Mg10 cuboctahedra that share corners with six equivalent Mg(4)Hf2Mg10 cuboctahedra, edges with four equivalent Hf(1)Mg10Cu2 cuboctahedra, faces with two equivalent Mg(4)Hf2Mg10 cuboctahedra, and faces with two equivalent Hf(1)Mg10Cu2 cuboctahedra. Hf(1) is bonded to two equivalent Mg(4), four equivalent Mg(1), four equivalent Mg(2), and two equivalent Cu(1) atoms to form distorted HfMg10Cu2 cuboctahedra that share corners with six equivalent Hf(1)Mg10Cu2 cuboctahedra, edges with four equivalent Mg(4)Hf2Mg10 cuboctahedra, faces with two equivalent Mg(4)Hf2Mg10 cuboctahedra, and faces with two equivalent Hf(1)Mg10Cu2 cuboctahedra. Cu(1) is bonded in a 10-coordinate geometry to two equivalent Mg(1), two equivalent Mg(3), four equivalent Mg(2), and two equivalent Hf(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_HfMg6Cu
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.906
_cell_length_b   5.938
_cell_length_c   6.414
_cell_angle_alpha   117.577
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   165.638
_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
  Cu  Cu0  1  0.500  0.152  0.305  1.0
  Hf  Hf1  1  0.500  0.682  0.363  1.0
  Mg  Mg2  1  0.500  0.681  0.859  1.0
  Mg  Mg3  1  0.500  0.178  0.859  1.0
  Mg  Mg4  1  0.000  0.831  0.164  1.0
  Mg  Mg5  1  1.000  0.333  0.164  1.0
  Mg  Mg6  1  0.000  0.310  0.620  1.0
  Mg  Mg7  1  0.000  0.833  0.667  1.0
[/CIF]
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