The compound described by Er2Mg crystallizes in the monoclinic Pm space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a distorted body-centered cubic geometry to two equivalent Er(1), two equivalent Er(2), and four equivalent Er(3) atoms. In the second Mg site, Mg(2) is bonded in a distorted body-centered cubic geometry to two equivalent Er(3), two equivalent Er(4), and four equivalent Er(1) atoms. There are four inequivalent Er sites. In the first Er site, Er(1) is bonded in a 6-coordinate geometry to two equivalent Mg(1), four equivalent Mg(2), two equivalent Er(2), and two equivalent Er(4) atoms. In the second Er site, Er(2) is bonded to two equivalent Mg(1), two equivalent Er(1), two equivalent Er(2), two equivalent Er(3), and four equivalent Er(4) atoms to form a mixture of distorted face, corner, and edge-sharing ErEr10Mg2 cuboctahedra. In the third Er site, Er(3) is bonded in a 6-coordinate geometry to two equivalent Mg(2), four equivalent Mg(1), two equivalent Er(2), and two equivalent Er(4) atoms. In the fourth Er site, Er(4) is bonded to two equivalent Mg(2), two equivalent Er(1), two equivalent Er(3), two equivalent Er(4), and four equivalent Er(2) atoms to form a mixture of distorted face, corner, and edge-sharing ErEr10Mg2 cuboctahedra. is represented by the CIF file [CIF]
data_Er2Mg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.652
_cell_length_b   8.691
_cell_length_c   5.387
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   77.851
_symmetry_Int_Tables_number   1
_cell_volume   167.127
_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  0.981  0.038  0.000  1.0
  Er  Er1  1  0.660  0.678  0.000  1.0
  Er  Er2  1  0.796  0.407  0.500  1.0
  Er  Er3  1  0.115  0.767  0.500  1.0
  Mg  Mg4  1  0.323  0.355  0.000  1.0
  Mg  Mg5  1  0.458  0.089  0.500  1.0
[/CIF]
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The compound described by Er2Mg crystallizes in the monoclinic Pm space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a distorted body-centered cubic geometry to two equivalent Er(1), two equivalent Er(2), and four equivalent Er(3) atoms. In the second Mg site, Mg(2) is bonded in a distorted body-centered cubic geometry to two equivalent Er(3), two equivalent Er(4), and four equivalent Er(1) atoms. There are four inequivalent Er sites. In the first Er site, Er(1) is bonded in a 6-coordinate geometry to two equivalent Mg(1), four equivalent Mg(2), two equivalent Er(2), and two equivalent Er(4) atoms. In the second Er site, Er(2) is bonded to two equivalent Mg(1), two equivalent Er(1), two equivalent Er(2), two equivalent Er(3), and four equivalent Er(4) atoms to form a mixture of distorted face, corner, and edge-sharing ErEr10Mg2 cuboctahedra. In the third Er site, Er(3) is bonded in a 6-coordinate geometry to two equivalent Mg(2), four equivalent Mg(1), two equivalent Er(2), and two equivalent Er(4) atoms. In the fourth Er site, Er(4) is bonded to two equivalent Mg(2), two equivalent Er(1), two equivalent Er(3), two equivalent Er(4), and four equivalent Er(2) atoms to form a mixture of distorted face, corner, and edge-sharing ErEr10Mg2 cuboctahedra. is represented by the CIF file [CIF]
data_Er2Mg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.652
_cell_length_b   8.691
_cell_length_c   5.387
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   77.851
_symmetry_Int_Tables_number   1
_cell_volume   167.127
_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  0.981  0.038  0.000  1.0
  Er  Er1  1  0.660  0.678  0.000  1.0
  Er  Er2  1  0.796  0.407  0.500  1.0
  Er  Er3  1  0.115  0.767  0.500  1.0
  Mg  Mg4  1  0.323  0.355  0.000  1.0
  Mg  Mg5  1  0.458  0.089  0.500  1.0
[/CIF]
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