The material structure described by MgY2 crystallizes in the monoclinic C2/m space group. Mg(1) is bonded in a 9-coordinate geometry to four equivalent Y(2) and five equivalent Y(1) atoms. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded to five equivalent Mg(1), three equivalent Y(2), and four equivalent Y(1) atoms to form distorted YY7Mg5 cuboctahedra that share corners with six equivalent Y(1)Y7Mg5 cuboctahedra, corners with six equivalent Y(2)Y8Mg4 cuboctahedra, edges with six equivalent Y(1)Y7Mg5 cuboctahedra, edges with seven equivalent Y(2)Y8Mg4 cuboctahedra, faces with five equivalent Y(1)Y7Mg5 cuboctahedra, and faces with seven equivalent Y(2)Y8Mg4 cuboctahedra. In the second Y site, Y(2) is bonded to four equivalent Mg(1), three equivalent Y(1), and five equivalent Y(2) atoms to form distorted YY8Mg4 cuboctahedra that share corners with six equivalent Y(1)Y7Mg5 cuboctahedra, corners with six equivalent Y(2)Y8Mg4 cuboctahedra, edges with two equivalent Y(2)Y8Mg4 cuboctahedra, edges with seven equivalent Y(1)Y7Mg5 cuboctahedra, faces with seven equivalent Y(1)Y7Mg5 cuboctahedra, and faces with seven equivalent Y(2)Y8Mg4 cuboctahedra. is represented by the CIF card [CIF]
data_Y2Mg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.579
_cell_length_b   6.579
_cell_length_c   8.068
_cell_angle_alpha   75.563
_cell_angle_beta   75.563
_cell_angle_gamma   31.596
_symmetry_Int_Tables_number   1
_cell_volume   176.732
_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  0.824  0.824  0.124  1.0
  Y  Y1  1  0.140  0.140  0.461  1.0
  Y  Y2  1  0.860  0.860  0.539  1.0
  Y  Y3  1  0.176  0.176  0.876  1.0
  Mg  Mg4  1  0.528  0.528  0.204  1.0
  Mg  Mg5  1  0.472  0.472  0.796  1.0
[/CIF]
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The material structure described by MgY2 crystallizes in the monoclinic C2/m space group. Mg(1) is bonded in a 9-coordinate geometry to four equivalent Y(2) and five equivalent Y(1) atoms. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded to five equivalent Mg(1), three equivalent Y(2), and four equivalent Y(1) atoms to form distorted YY7Mg5 cuboctahedra that share corners with six equivalent Y(1)Y7Mg5 cuboctahedra, corners with six equivalent Y(2)Y8Mg4 cuboctahedra, edges with six equivalent Y(1)Y7Mg5 cuboctahedra, edges with seven equivalent Y(2)Y8Mg4 cuboctahedra, faces with five equivalent Y(1)Y7Mg5 cuboctahedra, and faces with seven equivalent Y(2)Y8Mg4 cuboctahedra. In the second Y site, Y(2) is bonded to four equivalent Mg(1), three equivalent Y(1), and five equivalent Y(2) atoms to form distorted YY8Mg4 cuboctahedra that share corners with six equivalent Y(1)Y7Mg5 cuboctahedra, corners with six equivalent Y(2)Y8Mg4 cuboctahedra, edges with two equivalent Y(2)Y8Mg4 cuboctahedra, edges with seven equivalent Y(1)Y7Mg5 cuboctahedra, faces with seven equivalent Y(1)Y7Mg5 cuboctahedra, and faces with seven equivalent Y(2)Y8Mg4 cuboctahedra. is represented by the CIF card [CIF]
data_Y2Mg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.579
_cell_length_b   6.579
_cell_length_c   8.068
_cell_angle_alpha   75.563
_cell_angle_beta   75.563
_cell_angle_gamma   31.596
_symmetry_Int_Tables_number   1
_cell_volume   176.732
_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  0.824  0.824  0.124  1.0
  Y  Y1  1  0.140  0.140  0.461  1.0
  Y  Y2  1  0.860  0.860  0.539  1.0
  Y  Y3  1  0.176  0.176  0.876  1.0
  Mg  Mg4  1  0.528  0.528  0.204  1.0
  Mg  Mg5  1  0.472  0.472  0.796  1.0
[/CIF]
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