The compound described by MgY is beta-derived structured and crystallizes in the hexagonal P-6m2 space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to three equivalent Mg(2), six equivalent Mg(1), and three equivalent Y(2) atoms to form MgY3Mg9 cuboctahedra that share corners with six equivalent Y(1)Y12 cuboctahedra, corners with twelve equivalent Mg(1)Y3Mg9 cuboctahedra, edges with six equivalent Mg(2)Mg12 cuboctahedra, edges with six equivalent Mg(1)Y3Mg9 cuboctahedra, edges with six equivalent Y(2)Y9Mg3 cuboctahedra,  a faceface with one Y(1)Y12 cuboctahedra, faces with six equivalent Mg(2)Mg12 cuboctahedra, faces with six equivalent Y(2)Y9Mg3 cuboctahedra, and faces with seven equivalent Mg(1)Y3Mg9 cuboctahedra. In the second Mg site, Mg(2) is bonded to six equivalent Mg(1) and six equivalent Mg(2) atoms to form MgMg12 cuboctahedra that share corners with six equivalent Mg(2)Mg12 cuboctahedra, corners with twelve equivalent Y(2)Y9Mg3 cuboctahedra, edges with six equivalent Mg(2)Mg12 cuboctahedra, edges with twelve equivalent Mg(1)Y3Mg9 cuboctahedra, faces with two equivalent Y(2)Y9Mg3 cuboctahedra, faces with six equivalent Mg(2)Mg12 cuboctahedra, and faces with twelve equivalent Mg(1)Y3Mg9 cuboctahedra. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded to six equivalent Y(1) and six equivalent Y(2) atoms to form YY12 cuboctahedra that share corners with six equivalent Y(1)Y12 cuboctahedra, corners with twelve equivalent Mg(1)Y3Mg9 cuboctahedra, edges with six equivalent Y(1)Y12 cuboctahedra, edges with twelve equivalent Y(2)Y9Mg3 cuboctahedra, faces with two equivalent Mg(1)Y3Mg9 cuboctahedra, faces with six equivalent Y(1)Y12 cuboctahedra, and faces with twelve equivalent Y(2)Y9Mg3 cuboctahedra. In the second Y site, Y(2) is bonded to three equivalent Mg(1), three equivalent Y(1), and six equivalent Y(2) atoms to form YY9Mg3 cuboctahedra that share corners with six equivalent Mg(2)Mg12 cuboctahedra, corners with twelve equivalent Y(2)Y9Mg3 cuboctahedra, edges with six equivalent Mg(1)Y3Mg9 cuboctahedra, edges with six equivalent Y(1)Y12 cuboctahedra, edges with six equivalent Y(2)Y9Mg3 cuboctahedra,  a faceface with one Mg(2)Mg12 cuboctahedra, faces with six equivalent Mg(1)Y3Mg9 cuboctahedra, faces with six equivalent Y(1)Y12 cuboctahedra, and faces with seven equivalent Y(2)Y9Mg3 cuboctahedra. is represented by the CIF file [CIF]
data_YMg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.450
_cell_length_b   3.450
_cell_length_c   16.650
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   171.635
_cell_formula_units_Z   3
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  0.667  0.333  0.000  1.0
  Y  Y1  1  0.000  0.000  0.821  1.0
  Y  Y2  1  0.000  0.000  0.179  1.0
  Mg  Mg3  1  0.667  0.333  0.654  1.0
  Mg  Mg4  1  0.000  0.000  0.500  1.0
  Mg  Mg5  1  0.667  0.333  0.346  1.0
[/CIF]
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The compound described by MgY is beta-derived structured and crystallizes in the hexagonal P-6m2 space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to three equivalent Mg(2), six equivalent Mg(1), and three equivalent Y(2) atoms to form MgY3Mg9 cuboctahedra that share corners with six equivalent Y(1)Y12 cuboctahedra, corners with twelve equivalent Mg(1)Y3Mg9 cuboctahedra, edges with six equivalent Mg(2)Mg12 cuboctahedra, edges with six equivalent Mg(1)Y3Mg9 cuboctahedra, edges with six equivalent Y(2)Y9Mg3 cuboctahedra,  a faceface with one Y(1)Y12 cuboctahedra, faces with six equivalent Mg(2)Mg12 cuboctahedra, faces with six equivalent Y(2)Y9Mg3 cuboctahedra, and faces with seven equivalent Mg(1)Y3Mg9 cuboctahedra. In the second Mg site, Mg(2) is bonded to six equivalent Mg(1) and six equivalent Mg(2) atoms to form MgMg12 cuboctahedra that share corners with six equivalent Mg(2)Mg12 cuboctahedra, corners with twelve equivalent Y(2)Y9Mg3 cuboctahedra, edges with six equivalent Mg(2)Mg12 cuboctahedra, edges with twelve equivalent Mg(1)Y3Mg9 cuboctahedra, faces with two equivalent Y(2)Y9Mg3 cuboctahedra, faces with six equivalent Mg(2)Mg12 cuboctahedra, and faces with twelve equivalent Mg(1)Y3Mg9 cuboctahedra. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded to six equivalent Y(1) and six equivalent Y(2) atoms to form YY12 cuboctahedra that share corners with six equivalent Y(1)Y12 cuboctahedra, corners with twelve equivalent Mg(1)Y3Mg9 cuboctahedra, edges with six equivalent Y(1)Y12 cuboctahedra, edges with twelve equivalent Y(2)Y9Mg3 cuboctahedra, faces with two equivalent Mg(1)Y3Mg9 cuboctahedra, faces with six equivalent Y(1)Y12 cuboctahedra, and faces with twelve equivalent Y(2)Y9Mg3 cuboctahedra. In the second Y site, Y(2) is bonded to three equivalent Mg(1), three equivalent Y(1), and six equivalent Y(2) atoms to form YY9Mg3 cuboctahedra that share corners with six equivalent Mg(2)Mg12 cuboctahedra, corners with twelve equivalent Y(2)Y9Mg3 cuboctahedra, edges with six equivalent Mg(1)Y3Mg9 cuboctahedra, edges with six equivalent Y(1)Y12 cuboctahedra, edges with six equivalent Y(2)Y9Mg3 cuboctahedra,  a faceface with one Mg(2)Mg12 cuboctahedra, faces with six equivalent Mg(1)Y3Mg9 cuboctahedra, faces with six equivalent Y(1)Y12 cuboctahedra, and faces with seven equivalent Y(2)Y9Mg3 cuboctahedra. is represented by the CIF file [CIF]
data_YMg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.450
_cell_length_b   3.450
_cell_length_c   16.650
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   171.635
_cell_formula_units_Z   3
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  0.667  0.333  0.000  1.0
  Y  Y1  1  0.000  0.000  0.821  1.0
  Y  Y2  1  0.000  0.000  0.179  1.0
  Mg  Mg3  1  0.667  0.333  0.654  1.0
  Mg  Mg4  1  0.000  0.000  0.500  1.0
  Mg  Mg5  1  0.667  0.333  0.346  1.0
[/CIF]
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