The structure described by Rh5Mg crystallizes in the monoclinic Cm space group. Mg(1) is bonded to one Rh(3), two equivalent Rh(1), two equivalent Rh(2), two equivalent Rh(4), and three equivalent Rh(5) atoms to form distorted MgRh10 cuboctahedra that share corners with two equivalent Rh(1)Mg2Rh10 cuboctahedra, corners with four equivalent Mg(1)Rh10 cuboctahedra, corners with six equivalent Rh(2)Mg2Rh5 cuboctahedra, corners with eight equivalent Rh(4)Mg2Rh10 cuboctahedra,  an edgeedge with one Rh(4)Mg2Rh10 cuboctahedra, edges with two equivalent Rh(2)Mg2Rh5 cuboctahedra, edges with four equivalent Rh(1)Mg2Rh10 cuboctahedra, faces with two equivalent Mg(1)Rh10 cuboctahedra, faces with three equivalent Rh(1)Mg2Rh10 cuboctahedra, and faces with three equivalent Rh(4)Mg2Rh10 cuboctahedra. There are five inequivalent Rh sites. In the first Rh site, Rh(1) is bonded to two equivalent Mg(1), one Rh(4), two equivalent Rh(1), two equivalent Rh(3), two equivalent Rh(5), and three equivalent Rh(2) atoms to form distorted RhMg2Rh10 cuboctahedra that share corners with two equivalent Mg(1)Rh10 cuboctahedra, corners with two equivalent Rh(2)Mg2Rh5 cuboctahedra, corners with six equivalent Rh(1)Mg2Rh10 cuboctahedra, edges with four equivalent Mg(1)Rh10 cuboctahedra, edges with four equivalent Rh(4)Mg2Rh10 cuboctahedra, edges with five equivalent Rh(2)Mg2Rh5 cuboctahedra, faces with two equivalent Rh(1)Mg2Rh10 cuboctahedra, faces with three equivalent Mg(1)Rh10 cuboctahedra, and faces with four equivalent Rh(4)Mg2Rh10 cuboctahedra. In the second Rh site, Rh(2) is bonded to two equivalent Mg(1), two equivalent Rh(4), and three equivalent Rh(1) atoms to form distorted RhMg2Rh5 cuboctahedra that share corners with two equivalent Rh(1)Mg2Rh10 cuboctahedra, corners with four equivalent Rh(2)Mg2Rh5 cuboctahedra, corners with five equivalent Rh(4)Mg2Rh10 cuboctahedra, corners with six equivalent Mg(1)Rh10 cuboctahedra, edges with two equivalent Mg(1)Rh10 cuboctahedra, edges with three equivalent Rh(4)Mg2Rh10 cuboctahedra, edges with five equivalent Rh(1)Mg2Rh10 cuboctahedra, and faces with two equivalent Rh(2)Mg2Rh5 cuboctahedra. In the third Rh site, Rh(3) is bonded in a distorted single-bond geometry to one Mg(1), two equivalent Rh(1), and three equivalent Rh(4) atoms. In the fourth Rh site, Rh(4) is bonded to two equivalent Mg(1), one Rh(1), two equivalent Rh(2), two equivalent Rh(4), two equivalent Rh(5), and three equivalent Rh(3) atoms to form distorted RhMg2Rh10 cuboctahedra that share corners with five equivalent Rh(2)Mg2Rh5 cuboctahedra, corners with six equivalent Rh(4)Mg2Rh10 cuboctahedra, corners with eight equivalent Mg(1)Rh10 cuboctahedra,  an edgeedge with one Mg(1)Rh10 cuboctahedra, edges with three equivalent Rh(2)Mg2Rh5 cuboctahedra, edges with four equivalent Rh(1)Mg2Rh10 cuboctahedra, faces with two equivalent Rh(4)Mg2Rh10 cuboctahedra, faces with three equivalent Mg(1)Rh10 cuboctahedra, and faces with four equivalent Rh(1)Mg2Rh10 cuboctahedra. In the fifth Rh site, Rh(5) is bonded in a 3-coordinate geometry to three equivalent Mg(1), two equivalent Rh(1), and two equivalent Rh(4) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgRh5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.733
_cell_length_b   5.086
_cell_length_c   6.528
_cell_angle_alpha   76.025
_cell_angle_beta   90.000
_cell_angle_gamma   105.586
_symmetry_Int_Tables_number   1
_cell_volume   84.596
_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
  Mg  Mg0  1  0.385  0.771  0.722  1.0
  Rh  Rh1  1  0.006  0.011  0.002  1.0
  Rh  Rh2  1  0.725  0.450  0.056  1.0
  Rh  Rh3  1  0.333  0.666  0.330  1.0
  Rh  Rh4  1  0.058  0.115  0.388  1.0
  Rh  Rh5  1  0.660  0.320  0.670  1.0
[/CIF]
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The structure described by Rh5Mg crystallizes in the monoclinic Cm space group. Mg(1) is bonded to one Rh(3), two equivalent Rh(1), two equivalent Rh(2), two equivalent Rh(4), and three equivalent Rh(5) atoms to form distorted MgRh10 cuboctahedra that share corners with two equivalent Rh(1)Mg2Rh10 cuboctahedra, corners with four equivalent Mg(1)Rh10 cuboctahedra, corners with six equivalent Rh(2)Mg2Rh5 cuboctahedra, corners with eight equivalent Rh(4)Mg2Rh10 cuboctahedra,  an edgeedge with one Rh(4)Mg2Rh10 cuboctahedra, edges with two equivalent Rh(2)Mg2Rh5 cuboctahedra, edges with four equivalent Rh(1)Mg2Rh10 cuboctahedra, faces with two equivalent Mg(1)Rh10 cuboctahedra, faces with three equivalent Rh(1)Mg2Rh10 cuboctahedra, and faces with three equivalent Rh(4)Mg2Rh10 cuboctahedra. There are five inequivalent Rh sites. In the first Rh site, Rh(1) is bonded to two equivalent Mg(1), one Rh(4), two equivalent Rh(1), two equivalent Rh(3), two equivalent Rh(5), and three equivalent Rh(2) atoms to form distorted RhMg2Rh10 cuboctahedra that share corners with two equivalent Mg(1)Rh10 cuboctahedra, corners with two equivalent Rh(2)Mg2Rh5 cuboctahedra, corners with six equivalent Rh(1)Mg2Rh10 cuboctahedra, edges with four equivalent Mg(1)Rh10 cuboctahedra, edges with four equivalent Rh(4)Mg2Rh10 cuboctahedra, edges with five equivalent Rh(2)Mg2Rh5 cuboctahedra, faces with two equivalent Rh(1)Mg2Rh10 cuboctahedra, faces with three equivalent Mg(1)Rh10 cuboctahedra, and faces with four equivalent Rh(4)Mg2Rh10 cuboctahedra. In the second Rh site, Rh(2) is bonded to two equivalent Mg(1), two equivalent Rh(4), and three equivalent Rh(1) atoms to form distorted RhMg2Rh5 cuboctahedra that share corners with two equivalent Rh(1)Mg2Rh10 cuboctahedra, corners with four equivalent Rh(2)Mg2Rh5 cuboctahedra, corners with five equivalent Rh(4)Mg2Rh10 cuboctahedra, corners with six equivalent Mg(1)Rh10 cuboctahedra, edges with two equivalent Mg(1)Rh10 cuboctahedra, edges with three equivalent Rh(4)Mg2Rh10 cuboctahedra, edges with five equivalent Rh(1)Mg2Rh10 cuboctahedra, and faces with two equivalent Rh(2)Mg2Rh5 cuboctahedra. In the third Rh site, Rh(3) is bonded in a distorted single-bond geometry to one Mg(1), two equivalent Rh(1), and three equivalent Rh(4) atoms. In the fourth Rh site, Rh(4) is bonded to two equivalent Mg(1), one Rh(1), two equivalent Rh(2), two equivalent Rh(4), two equivalent Rh(5), and three equivalent Rh(3) atoms to form distorted RhMg2Rh10 cuboctahedra that share corners with five equivalent Rh(2)Mg2Rh5 cuboctahedra, corners with six equivalent Rh(4)Mg2Rh10 cuboctahedra, corners with eight equivalent Mg(1)Rh10 cuboctahedra,  an edgeedge with one Mg(1)Rh10 cuboctahedra, edges with three equivalent Rh(2)Mg2Rh5 cuboctahedra, edges with four equivalent Rh(1)Mg2Rh10 cuboctahedra, faces with two equivalent Rh(4)Mg2Rh10 cuboctahedra, faces with three equivalent Mg(1)Rh10 cuboctahedra, and faces with four equivalent Rh(1)Mg2Rh10 cuboctahedra. In the fifth Rh site, Rh(5) is bonded in a 3-coordinate geometry to three equivalent Mg(1), two equivalent Rh(1), and two equivalent Rh(4) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgRh5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.733
_cell_length_b   5.086
_cell_length_c   6.528
_cell_angle_alpha   76.025
_cell_angle_beta   90.000
_cell_angle_gamma   105.586
_symmetry_Int_Tables_number   1
_cell_volume   84.596
_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
  Mg  Mg0  1  0.385  0.771  0.722  1.0
  Rh  Rh1  1  0.006  0.011  0.002  1.0
  Rh  Rh2  1  0.725  0.450  0.056  1.0
  Rh  Rh3  1  0.333  0.666  0.330  1.0
  Rh  Rh4  1  0.058  0.115  0.388  1.0
  Rh  Rh5  1  0.660  0.320  0.670  1.0
[/CIF]
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