The compound described by Mg2Y is beta-derived structured and crystallizes in the monoclinic C2/m space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to four equivalent Mg(2), five equivalent Mg(1), and three equivalent Y(1) atoms to form distorted MgY3Mg9 cuboctahedra that share corners with six equivalent Mg(1)Y3Mg9 cuboctahedra, corners with six equivalent Mg(2)Y5Mg7 cuboctahedra, corners with six equivalent Y(1)Y4Mg8 cuboctahedra, edges with two equivalent Mg(1)Y3Mg9 cuboctahedra, edges with seven equivalent Y(1)Y4Mg8 cuboctahedra, edges with nine equivalent Mg(2)Y5Mg7 cuboctahedra, faces with six equivalent Mg(2)Y5Mg7 cuboctahedra, faces with seven equivalent Mg(1)Y3Mg9 cuboctahedra, and faces with seven equivalent Y(1)Y4Mg8 cuboctahedra. In the second Mg site, Mg(2) is bonded to three equivalent Mg(2), four equivalent Mg(1), and five equivalent Y(1) atoms to form distorted MgY5Mg7 cuboctahedra that share corners with six equivalent Mg(1)Y3Mg9 cuboctahedra, corners with six equivalent Mg(2)Y5Mg7 cuboctahedra, corners with six equivalent Y(1)Y4Mg8 cuboctahedra, edges with four equivalent Mg(2)Y5Mg7 cuboctahedra, edges with five equivalent Y(1)Y4Mg8 cuboctahedra, edges with nine equivalent Mg(1)Y3Mg9 cuboctahedra, faces with six equivalent Mg(1)Y3Mg9 cuboctahedra, faces with six equivalent Mg(2)Y5Mg7 cuboctahedra, and faces with eight equivalent Y(1)Y4Mg8 cuboctahedra. Y(1) is bonded to three equivalent Mg(1), five equivalent Mg(2), and four equivalent Y(1) atoms to form YY4Mg8 cuboctahedra that share corners with six equivalent Mg(1)Y3Mg9 cuboctahedra, corners with six equivalent Mg(2)Y5Mg7 cuboctahedra, corners with six equivalent Y(1)Y4Mg8 cuboctahedra, edges with five equivalent Mg(2)Y5Mg7 cuboctahedra, edges with six equivalent Y(1)Y4Mg8 cuboctahedra, edges with seven equivalent Mg(1)Y3Mg9 cuboctahedra, faces with five equivalent Y(1)Y4Mg8 cuboctahedra, faces with seven equivalent Mg(1)Y3Mg9 cuboctahedra, and faces with eight equivalent Mg(2)Y5Mg7 cuboctahedra. is represented by the CIF card [CIF]
data_YMg2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.615
_cell_length_b   6.615
_cell_length_c   7.823
_cell_angle_alpha   75.185
_cell_angle_beta   75.185
_cell_angle_gamma   28.953
_symmetry_Int_Tables_number   1
_cell_volume   159.811
_cell_formula_units_Z   2
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  0.811  0.811  0.640  1.0
  Y  Y1  1  0.189  0.189  0.360  1.0
  Mg  Mg2  1  0.134  0.134  0.976  1.0
  Mg  Mg3  1  0.531  0.531  0.703  1.0
  Mg  Mg4  1  0.469  0.469  0.297  1.0
  Mg  Mg5  1  0.866  0.866  0.024  1.0
[/CIF]
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The compound described by Mg2Y is beta-derived structured and crystallizes in the monoclinic C2/m space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to four equivalent Mg(2), five equivalent Mg(1), and three equivalent Y(1) atoms to form distorted MgY3Mg9 cuboctahedra that share corners with six equivalent Mg(1)Y3Mg9 cuboctahedra, corners with six equivalent Mg(2)Y5Mg7 cuboctahedra, corners with six equivalent Y(1)Y4Mg8 cuboctahedra, edges with two equivalent Mg(1)Y3Mg9 cuboctahedra, edges with seven equivalent Y(1)Y4Mg8 cuboctahedra, edges with nine equivalent Mg(2)Y5Mg7 cuboctahedra, faces with six equivalent Mg(2)Y5Mg7 cuboctahedra, faces with seven equivalent Mg(1)Y3Mg9 cuboctahedra, and faces with seven equivalent Y(1)Y4Mg8 cuboctahedra. In the second Mg site, Mg(2) is bonded to three equivalent Mg(2), four equivalent Mg(1), and five equivalent Y(1) atoms to form distorted MgY5Mg7 cuboctahedra that share corners with six equivalent Mg(1)Y3Mg9 cuboctahedra, corners with six equivalent Mg(2)Y5Mg7 cuboctahedra, corners with six equivalent Y(1)Y4Mg8 cuboctahedra, edges with four equivalent Mg(2)Y5Mg7 cuboctahedra, edges with five equivalent Y(1)Y4Mg8 cuboctahedra, edges with nine equivalent Mg(1)Y3Mg9 cuboctahedra, faces with six equivalent Mg(1)Y3Mg9 cuboctahedra, faces with six equivalent Mg(2)Y5Mg7 cuboctahedra, and faces with eight equivalent Y(1)Y4Mg8 cuboctahedra. Y(1) is bonded to three equivalent Mg(1), five equivalent Mg(2), and four equivalent Y(1) atoms to form YY4Mg8 cuboctahedra that share corners with six equivalent Mg(1)Y3Mg9 cuboctahedra, corners with six equivalent Mg(2)Y5Mg7 cuboctahedra, corners with six equivalent Y(1)Y4Mg8 cuboctahedra, edges with five equivalent Mg(2)Y5Mg7 cuboctahedra, edges with six equivalent Y(1)Y4Mg8 cuboctahedra, edges with seven equivalent Mg(1)Y3Mg9 cuboctahedra, faces with five equivalent Y(1)Y4Mg8 cuboctahedra, faces with seven equivalent Mg(1)Y3Mg9 cuboctahedra, and faces with eight equivalent Mg(2)Y5Mg7 cuboctahedra. is represented by the CIF card [CIF]
data_YMg2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.615
_cell_length_b   6.615
_cell_length_c   7.823
_cell_angle_alpha   75.185
_cell_angle_beta   75.185
_cell_angle_gamma   28.953
_symmetry_Int_Tables_number   1
_cell_volume   159.811
_cell_formula_units_Z   2
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  0.811  0.811  0.640  1.0
  Y  Y1  1  0.189  0.189  0.360  1.0
  Mg  Mg2  1  0.134  0.134  0.976  1.0
  Mg  Mg3  1  0.531  0.531  0.703  1.0
  Mg  Mg4  1  0.469  0.469  0.297  1.0
  Mg  Mg5  1  0.866  0.866  0.024  1.0
[/CIF]
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