The compound described by Mg5Eu crystallizes in the hexagonal P-62m space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a distorted q6 geometry to four equivalent Mg(1), four equivalent Mg(2), and two equivalent Eu(1) atoms. In the second Mg site, Mg(2) is bonded to six equivalent Mg(1) and three equivalent Eu(1) atoms to form distorted MgEu3Mg6 cuboctahedra that share corners with six equivalent Eu(1)Mg12 cuboctahedra, corners with fifteen equivalent Mg(2)Eu3Mg6 cuboctahedra, edges with three equivalent Eu(1)Mg12 cuboctahedra, and faces with five equivalent Mg(2)Eu3Mg6 cuboctahedra. Eu(1) is bonded to six equivalent Mg(1) and six equivalent Mg(2) atoms to form EuMg12 cuboctahedra that share corners with twelve equivalent Mg(2)Eu3Mg6 cuboctahedra, edges with six equivalent Mg(2)Eu3Mg6 cuboctahedra, edges with six equivalent Eu(1)Mg12 cuboctahedra, and faces with two equivalent Eu(1)Mg12 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_EuMg5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.052
_cell_length_b   6.052
_cell_length_c   5.038
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   159.808
_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
  Eu  Eu0  1  0.000  0.000  0.500  1.0
  Mg  Mg1  1  0.000  0.549  0.000  1.0
  Mg  Mg2  1  0.333  0.667  0.500  1.0
  Mg  Mg3  1  0.549  0.000  0.000  1.0
  Mg  Mg4  1  0.667  0.333  0.500  1.0
  Mg  Mg5  1  0.451  0.451  0.000  1.0
[/CIF]
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The compound described by Mg5Eu crystallizes in the hexagonal P-62m space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a distorted q6 geometry to four equivalent Mg(1), four equivalent Mg(2), and two equivalent Eu(1) atoms. In the second Mg site, Mg(2) is bonded to six equivalent Mg(1) and three equivalent Eu(1) atoms to form distorted MgEu3Mg6 cuboctahedra that share corners with six equivalent Eu(1)Mg12 cuboctahedra, corners with fifteen equivalent Mg(2)Eu3Mg6 cuboctahedra, edges with three equivalent Eu(1)Mg12 cuboctahedra, and faces with five equivalent Mg(2)Eu3Mg6 cuboctahedra. Eu(1) is bonded to six equivalent Mg(1) and six equivalent Mg(2) atoms to form EuMg12 cuboctahedra that share corners with twelve equivalent Mg(2)Eu3Mg6 cuboctahedra, edges with six equivalent Mg(2)Eu3Mg6 cuboctahedra, edges with six equivalent Eu(1)Mg12 cuboctahedra, and faces with two equivalent Eu(1)Mg12 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_EuMg5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.052
_cell_length_b   6.052
_cell_length_c   5.038
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   159.808
_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
  Eu  Eu0  1  0.000  0.000  0.500  1.0
  Mg  Mg1  1  0.000  0.549  0.000  1.0
  Mg  Mg2  1  0.333  0.667  0.500  1.0
  Mg  Mg3  1  0.549  0.000  0.000  1.0
  Mg  Mg4  1  0.667  0.333  0.500  1.0
  Mg  Mg5  1  0.451  0.451  0.000  1.0
[/CIF]
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