The compound described by MgEr3 is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/mmc space group. Mg(1) is bonded to twelve equivalent Er(1) atoms to form MgEr12 cuboctahedra that share corners with six equivalent Mg(1)Er12 cuboctahedra, corners with twelve equivalent Er(1)Er8Mg4 cuboctahedra, edges with eighteen equivalent Er(1)Er8Mg4 cuboctahedra, faces with eight equivalent Mg(1)Er12 cuboctahedra, and faces with twelve equivalent Er(1)Er8Mg4 cuboctahedra. Er(1) is bonded to four equivalent Mg(1) and eight equivalent Er(1) atoms to form ErEr8Mg4 cuboctahedra that share corners with four equivalent Mg(1)Er12 cuboctahedra, corners with fourteen equivalent Er(1)Er8Mg4 cuboctahedra, edges with six equivalent Mg(1)Er12 cuboctahedra, edges with twelve equivalent Er(1)Er8Mg4 cuboctahedra, faces with four equivalent Mg(1)Er12 cuboctahedra, and faces with sixteen equivalent Er(1)Er8Mg4 cuboctahedra. is represented by the CIF card [CIF]
data_Er3Mg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.935
_cell_length_b   6.935
_cell_length_c   5.498
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   228.972
_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
  Er  Er0  1  0.170  0.339  0.250  1.0
  Er  Er1  1  0.170  0.830  0.250  1.0
  Er  Er2  1  0.661  0.830  0.250  1.0
  Er  Er3  1  0.339  0.170  0.750  1.0
  Er  Er4  1  0.830  0.170  0.750  1.0
  Er  Er5  1  0.830  0.661  0.750  1.0
  Mg  Mg6  1  0.667  0.333  0.250  1.0
  Mg  Mg7  1  0.333  0.667  0.750  1.0
[/CIF]
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The compound described by MgEr3 is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/mmc space group. Mg(1) is bonded to twelve equivalent Er(1) atoms to form MgEr12 cuboctahedra that share corners with six equivalent Mg(1)Er12 cuboctahedra, corners with twelve equivalent Er(1)Er8Mg4 cuboctahedra, edges with eighteen equivalent Er(1)Er8Mg4 cuboctahedra, faces with eight equivalent Mg(1)Er12 cuboctahedra, and faces with twelve equivalent Er(1)Er8Mg4 cuboctahedra. Er(1) is bonded to four equivalent Mg(1) and eight equivalent Er(1) atoms to form ErEr8Mg4 cuboctahedra that share corners with four equivalent Mg(1)Er12 cuboctahedra, corners with fourteen equivalent Er(1)Er8Mg4 cuboctahedra, edges with six equivalent Mg(1)Er12 cuboctahedra, edges with twelve equivalent Er(1)Er8Mg4 cuboctahedra, faces with four equivalent Mg(1)Er12 cuboctahedra, and faces with sixteen equivalent Er(1)Er8Mg4 cuboctahedra. is represented by the CIF card [CIF]
data_Er3Mg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.935
_cell_length_b   6.935
_cell_length_c   5.498
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   228.972
_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
  Er  Er0  1  0.170  0.339  0.250  1.0
  Er  Er1  1  0.170  0.830  0.250  1.0
  Er  Er2  1  0.661  0.830  0.250  1.0
  Er  Er3  1  0.339  0.170  0.750  1.0
  Er  Er4  1  0.830  0.170  0.750  1.0
  Er  Er5  1  0.830  0.661  0.750  1.0
  Mg  Mg6  1  0.667  0.333  0.250  1.0
  Mg  Mg7  1  0.333  0.667  0.750  1.0
[/CIF]
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