The compound described by Mg5Er is Magnesium-derived structured and crystallizes in the orthorhombic Amm2 space group. There are five inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(5), and four equivalent Mg(4) atoms to form MgMg12 cuboctahedra that share corners with six equivalent Mg(3)Er2Mg10 cuboctahedra, corners with six equivalent Mg(2)Er4Mg8 cuboctahedra, corners with six equivalent Mg(1)Mg12 cuboctahedra, edges with three equivalent Mg(3)Er2Mg10 cuboctahedra, edges with three equivalent Mg(2)Er4Mg8 cuboctahedra, edges with four equivalent Mg(4)Er2Mg10 cuboctahedra, edges with eight equivalent Er(1)Er2Mg10 cuboctahedra, faces with two equivalent Mg(3)Er2Mg10 cuboctahedra, faces with two equivalent Mg(2)Er4Mg8 cuboctahedra, faces with two equivalent Er(1)Er2Mg10 cuboctahedra, faces with four equivalent Mg(4)Er2Mg10 cuboctahedra, faces with four equivalent Mg(1)Mg12 cuboctahedra, and faces with six equivalent Mg(5)Er2Mg10 cuboctahedra. In the second Mg site, Mg(2) is bonded to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), and four equivalent Er(1) atoms to form MgEr4Mg8 cuboctahedra that share corners with six equivalent Mg(3)Er2Mg10 cuboctahedra, corners with six equivalent Mg(2)Er4Mg8 cuboctahedra, corners with six equivalent Mg(1)Mg12 cuboctahedra, edges with three equivalent Mg(3)Er2Mg10 cuboctahedra, edges with three equivalent Mg(1)Mg12 cuboctahedra, edges with four equivalent Er(1)Er2Mg10 cuboctahedra, edges with eight equivalent Mg(5)Er2Mg10 cuboctahedra, faces with two equivalent Mg(3)Er2Mg10 cuboctahedra, faces with two equivalent Mg(5)Er2Mg10 cuboctahedra, faces with two equivalent Mg(1)Mg12 cuboctahedra, faces with four equivalent Mg(2)Er4Mg8 cuboctahedra, faces with four equivalent Er(1)Er2Mg10 cuboctahedra, and faces with six equivalent Mg(4)Er2Mg10 cuboctahedra. In the third Mg site, Mg(3) is bonded to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), four equivalent Mg(5), and two equivalent Er(1) atoms to form MgEr2Mg10 cuboctahedra that share corners with six equivalent Mg(3)Er2Mg10 cuboctahedra, corners with six equivalent Mg(2)Er4Mg8 cuboctahedra, corners with six equivalent Mg(1)Mg12 cuboctahedra, edges with three equivalent Mg(2)Er4Mg8 cuboctahedra, edges with three equivalent Mg(1)Mg12 cuboctahedra, edges with four equivalent Mg(5)Er2Mg10 cuboctahedra, edges with eight equivalent Mg(4)Er2Mg10 cuboctahedra, faces with two equivalent Mg(4)Er2Mg10 cuboctahedra, faces with two equivalent Mg(2)Er4Mg8 cuboctahedra, faces with two equivalent Mg(1)Mg12 cuboctahedra, faces with four equivalent Mg(3)Er2Mg10 cuboctahedra, faces with four equivalent Mg(5)Er2Mg10 cuboctahedra, and faces with six equivalent Er(1)Er2Mg10 cuboctahedra. In the fourth Mg site, Mg(4) is bonded to two equivalent Mg(2), two equivalent Mg(4), two equivalent Mg(5), four equivalent Mg(1), and two equivalent Er(1) atoms to form MgEr2Mg10 cuboctahedra that share corners with six equivalent Mg(4)Er2Mg10 cuboctahedra, corners with six equivalent Mg(5)Er2Mg10 cuboctahedra, corners with six equivalent Er(1)Er2Mg10 cuboctahedra, edges with three equivalent Mg(5)Er2Mg10 cuboctahedra, edges with three equivalent Er(1)Er2Mg10 cuboctahedra, edges with four equivalent Mg(1)Mg12 cuboctahedra, edges with eight equivalent Mg(3)Er2Mg10 cuboctahedra, faces with two equivalent Mg(3)Er2Mg10 cuboctahedra, faces with two equivalent Mg(5)Er2Mg10 cuboctahedra, faces with two equivalent Er(1)Er2Mg10 cuboctahedra, faces with four equivalent Mg(4)Er2Mg10 cuboctahedra, faces with four equivalent Mg(1)Mg12 cuboctahedra, and faces with six equivalent Mg(2)Er4Mg8 cuboctahedra. In the fifth Mg site, Mg(5) is bonded to two equivalent Mg(1), two equivalent Mg(4), two equivalent Mg(5), four equivalent Mg(3), and two equivalent Er(1) atoms to form MgEr2Mg10 cuboctahedra that share corners with six equivalent Mg(4)Er2Mg10 cuboctahedra, corners with six equivalent Mg(5)Er2Mg10 cuboctahedra, corners with six equivalent Er(1)Er2Mg10 cuboctahedra, edges with three equivalent Mg(4)Er2Mg10 cuboctahedra, edges with three equivalent Er(1)Er2Mg10 cuboctahedra, edges with four equivalent Mg(3)Er2Mg10 cuboctahedra, edges with eight equivalent Mg(2)Er4Mg8 cuboctahedra, faces with two equivalent Mg(4)Er2Mg10 cuboctahedra, faces with two equivalent Mg(2)Er4Mg8 cuboctahedra, faces with two equivalent Er(1)Er2Mg10 cuboctahedra, faces with four equivalent Mg(3)Er2Mg10 cuboctahedra, faces with four equivalent Mg(5)Er2Mg10 cuboctahedra, and faces with six equivalent Mg(1)Mg12 cuboctahedra. Er(1) is bonded to two equivalent Mg(3), two equivalent Mg(4), two equivalent Mg(5), four equivalent Mg(2), and two equivalent Er(1) atoms to form ErEr2Mg10 cuboctahedra that share corners with six equivalent Mg(4)Er2Mg10 cuboctahedra, corners with six equivalent Mg(5)Er2Mg10 cuboctahedra, corners with six equivalent Er(1)Er2Mg10 cuboctahedra, edges with three equivalent Mg(4)Er2Mg10 cuboctahedra, edges with three equivalent Mg(5)Er2Mg10 cuboctahedra, edges with four equivalent Mg(2)Er4Mg8 cuboctahedra, edges with eight equivalent Mg(1)Mg12 cuboctahedra, faces with two equivalent Mg(4)Er2Mg10 cuboctahedra, faces with two equivalent Mg(5)Er2Mg10 cuboctahedra, faces with two equivalent Mg(1)Mg12 cuboctahedra, faces with four equivalent Mg(2)Er4Mg8 cuboctahedra, faces with four equivalent Er(1)Er2Mg10 cuboctahedra, and faces with six equivalent Mg(3)Er2Mg10 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_ErMg5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.693
_cell_length_b   8.693
_cell_length_c   5.267
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   158.676
_symmetry_Int_Tables_number   1
_cell_volume   144.705
_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
  Er  Er0  1  0.221  0.779  0.000  1.0
  Mg  Mg1  1  0.002  0.998  0.500  1.0
  Mg  Mg2  1  0.663  0.337  0.500  1.0
  Mg  Mg3  1  0.334  0.666  0.500  1.0
  Mg  Mg4  1  0.553  0.447  0.000  1.0
  Mg  Mg5  1  0.893  0.107  0.000  1.0
[/CIF]
.
The compound described by Mg5Er is Magnesium-derived structured and crystallizes in the orthorhombic Amm2 space group. There are five inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(5), and four equivalent Mg(4) atoms to form MgMg12 cuboctahedra that share corners with six equivalent Mg(3)Er2Mg10 cuboctahedra, corners with six equivalent Mg(2)Er4Mg8 cuboctahedra, corners with six equivalent Mg(1)Mg12 cuboctahedra, edges with three equivalent Mg(3)Er2Mg10 cuboctahedra, edges with three equivalent Mg(2)Er4Mg8 cuboctahedra, edges with four equivalent Mg(4)Er2Mg10 cuboctahedra, edges with eight equivalent Er(1)Er2Mg10 cuboctahedra, faces with two equivalent Mg(3)Er2Mg10 cuboctahedra, faces with two equivalent Mg(2)Er4Mg8 cuboctahedra, faces with two equivalent Er(1)Er2Mg10 cuboctahedra, faces with four equivalent Mg(4)Er2Mg10 cuboctahedra, faces with four equivalent Mg(1)Mg12 cuboctahedra, and faces with six equivalent Mg(5)Er2Mg10 cuboctahedra. In the second Mg site, Mg(2) is bonded to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), and four equivalent Er(1) atoms to form MgEr4Mg8 cuboctahedra that share corners with six equivalent Mg(3)Er2Mg10 cuboctahedra, corners with six equivalent Mg(2)Er4Mg8 cuboctahedra, corners with six equivalent Mg(1)Mg12 cuboctahedra, edges with three equivalent Mg(3)Er2Mg10 cuboctahedra, edges with three equivalent Mg(1)Mg12 cuboctahedra, edges with four equivalent Er(1)Er2Mg10 cuboctahedra, edges with eight equivalent Mg(5)Er2Mg10 cuboctahedra, faces with two equivalent Mg(3)Er2Mg10 cuboctahedra, faces with two equivalent Mg(5)Er2Mg10 cuboctahedra, faces with two equivalent Mg(1)Mg12 cuboctahedra, faces with four equivalent Mg(2)Er4Mg8 cuboctahedra, faces with four equivalent Er(1)Er2Mg10 cuboctahedra, and faces with six equivalent Mg(4)Er2Mg10 cuboctahedra. In the third Mg site, Mg(3) is bonded to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), four equivalent Mg(5), and two equivalent Er(1) atoms to form MgEr2Mg10 cuboctahedra that share corners with six equivalent Mg(3)Er2Mg10 cuboctahedra, corners with six equivalent Mg(2)Er4Mg8 cuboctahedra, corners with six equivalent Mg(1)Mg12 cuboctahedra, edges with three equivalent Mg(2)Er4Mg8 cuboctahedra, edges with three equivalent Mg(1)Mg12 cuboctahedra, edges with four equivalent Mg(5)Er2Mg10 cuboctahedra, edges with eight equivalent Mg(4)Er2Mg10 cuboctahedra, faces with two equivalent Mg(4)Er2Mg10 cuboctahedra, faces with two equivalent Mg(2)Er4Mg8 cuboctahedra, faces with two equivalent Mg(1)Mg12 cuboctahedra, faces with four equivalent Mg(3)Er2Mg10 cuboctahedra, faces with four equivalent Mg(5)Er2Mg10 cuboctahedra, and faces with six equivalent Er(1)Er2Mg10 cuboctahedra. In the fourth Mg site, Mg(4) is bonded to two equivalent Mg(2), two equivalent Mg(4), two equivalent Mg(5), four equivalent Mg(1), and two equivalent Er(1) atoms to form MgEr2Mg10 cuboctahedra that share corners with six equivalent Mg(4)Er2Mg10 cuboctahedra, corners with six equivalent Mg(5)Er2Mg10 cuboctahedra, corners with six equivalent Er(1)Er2Mg10 cuboctahedra, edges with three equivalent Mg(5)Er2Mg10 cuboctahedra, edges with three equivalent Er(1)Er2Mg10 cuboctahedra, edges with four equivalent Mg(1)Mg12 cuboctahedra, edges with eight equivalent Mg(3)Er2Mg10 cuboctahedra, faces with two equivalent Mg(3)Er2Mg10 cuboctahedra, faces with two equivalent Mg(5)Er2Mg10 cuboctahedra, faces with two equivalent Er(1)Er2Mg10 cuboctahedra, faces with four equivalent Mg(4)Er2Mg10 cuboctahedra, faces with four equivalent Mg(1)Mg12 cuboctahedra, and faces with six equivalent Mg(2)Er4Mg8 cuboctahedra. In the fifth Mg site, Mg(5) is bonded to two equivalent Mg(1), two equivalent Mg(4), two equivalent Mg(5), four equivalent Mg(3), and two equivalent Er(1) atoms to form MgEr2Mg10 cuboctahedra that share corners with six equivalent Mg(4)Er2Mg10 cuboctahedra, corners with six equivalent Mg(5)Er2Mg10 cuboctahedra, corners with six equivalent Er(1)Er2Mg10 cuboctahedra, edges with three equivalent Mg(4)Er2Mg10 cuboctahedra, edges with three equivalent Er(1)Er2Mg10 cuboctahedra, edges with four equivalent Mg(3)Er2Mg10 cuboctahedra, edges with eight equivalent Mg(2)Er4Mg8 cuboctahedra, faces with two equivalent Mg(4)Er2Mg10 cuboctahedra, faces with two equivalent Mg(2)Er4Mg8 cuboctahedra, faces with two equivalent Er(1)Er2Mg10 cuboctahedra, faces with four equivalent Mg(3)Er2Mg10 cuboctahedra, faces with four equivalent Mg(5)Er2Mg10 cuboctahedra, and faces with six equivalent Mg(1)Mg12 cuboctahedra. Er(1) is bonded to two equivalent Mg(3), two equivalent Mg(4), two equivalent Mg(5), four equivalent Mg(2), and two equivalent Er(1) atoms to form ErEr2Mg10 cuboctahedra that share corners with six equivalent Mg(4)Er2Mg10 cuboctahedra, corners with six equivalent Mg(5)Er2Mg10 cuboctahedra, corners with six equivalent Er(1)Er2Mg10 cuboctahedra, edges with three equivalent Mg(4)Er2Mg10 cuboctahedra, edges with three equivalent Mg(5)Er2Mg10 cuboctahedra, edges with four equivalent Mg(2)Er4Mg8 cuboctahedra, edges with eight equivalent Mg(1)Mg12 cuboctahedra, faces with two equivalent Mg(4)Er2Mg10 cuboctahedra, faces with two equivalent Mg(5)Er2Mg10 cuboctahedra, faces with two equivalent Mg(1)Mg12 cuboctahedra, faces with four equivalent Mg(2)Er4Mg8 cuboctahedra, faces with four equivalent Er(1)Er2Mg10 cuboctahedra, and faces with six equivalent Mg(3)Er2Mg10 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_ErMg5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.693
_cell_length_b   8.693
_cell_length_c   5.267
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   158.676
_symmetry_Int_Tables_number   1
_cell_volume   144.705
_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
  Er  Er0  1  0.221  0.779  0.000  1.0
  Mg  Mg1  1  0.002  0.998  0.500  1.0
  Mg  Mg2  1  0.663  0.337  0.500  1.0
  Mg  Mg3  1  0.334  0.666  0.500  1.0
  Mg  Mg4  1  0.553  0.447  0.000  1.0
  Mg  Mg5  1  0.893  0.107  0.000  1.0
[/CIF]
.