The compound described by Mg2Y is Hexagonal Laves structured and crystallizes in the hexagonal P6_3/mmc space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to six equivalent Mg(2) and six equivalent Y(1) atoms to form a mixture of face, corner, and edge-sharing MgY6Mg6 cuboctahedra. In the second Mg site, Mg(2) is bonded to two equivalent Mg(1), four equivalent Mg(2), and six equivalent Y(1) atoms to form a mixture of face, corner, and edge-sharing MgY6Mg6 cuboctahedra. Y(1) is bonded in a 16-coordinate geometry to three equivalent Mg(1), nine equivalent Mg(2), and four equivalent Y(1) atoms. is represented by the CIF file [CIF]
data_YMg2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.048
_cell_length_b   6.048
_cell_length_c   9.850
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   312.009
_cell_formula_units_Z   4
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  0.333  0.667  0.064  1.0
  Y  Y1  1  0.667  0.333  0.564  1.0
  Y  Y2  1  0.667  0.333  0.936  1.0
  Y  Y3  1  0.333  0.667  0.436  1.0
  Mg  Mg4  1  0.000  0.000  0.000  1.0
  Mg  Mg5  1  0.000  0.000  0.500  1.0
  Mg  Mg6  1  0.829  0.658  0.250  1.0
  Mg  Mg7  1  0.171  0.829  0.750  1.0
  Mg  Mg8  1  0.658  0.829  0.750  1.0
  Mg  Mg9  1  0.342  0.171  0.250  1.0
  Mg  Mg10  1  0.829  0.171  0.250  1.0
  Mg  Mg11  1  0.171  0.342  0.750  1.0
[/CIF]
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The compound described by Mg2Y is Hexagonal Laves structured and crystallizes in the hexagonal P6_3/mmc space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to six equivalent Mg(2) and six equivalent Y(1) atoms to form a mixture of face, corner, and edge-sharing MgY6Mg6 cuboctahedra. In the second Mg site, Mg(2) is bonded to two equivalent Mg(1), four equivalent Mg(2), and six equivalent Y(1) atoms to form a mixture of face, corner, and edge-sharing MgY6Mg6 cuboctahedra. Y(1) is bonded in a 16-coordinate geometry to three equivalent Mg(1), nine equivalent Mg(2), and four equivalent Y(1) atoms. is represented by the CIF file [CIF]
data_YMg2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.048
_cell_length_b   6.048
_cell_length_c   9.850
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   312.009
_cell_formula_units_Z   4
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  0.333  0.667  0.064  1.0
  Y  Y1  1  0.667  0.333  0.564  1.0
  Y  Y2  1  0.667  0.333  0.936  1.0
  Y  Y3  1  0.333  0.667  0.436  1.0
  Mg  Mg4  1  0.000  0.000  0.000  1.0
  Mg  Mg5  1  0.000  0.000  0.500  1.0
  Mg  Mg6  1  0.829  0.658  0.250  1.0
  Mg  Mg7  1  0.171  0.829  0.750  1.0
  Mg  Mg8  1  0.658  0.829  0.750  1.0
  Mg  Mg9  1  0.342  0.171  0.250  1.0
  Mg  Mg10  1  0.829  0.171  0.250  1.0
  Mg  Mg11  1  0.171  0.342  0.750  1.0
[/CIF]
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