The crystal structure described by Tm2Mg 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 Tm(1), two equivalent Tm(2), and four equivalent Tm(3) atoms. In the second Mg site, Mg(2) is bonded in a distorted body-centered cubic geometry to two equivalent Tm(3), two equivalent Tm(4), and four equivalent Tm(1) atoms. There are four inequivalent Tm sites. In the first Tm site, Tm(1) is bonded in a 6-coordinate geometry to two equivalent Mg(1), four equivalent Mg(2), two equivalent Tm(2), and two equivalent Tm(4) atoms. In the second Tm site, Tm(2) is bonded to two equivalent Mg(1), two equivalent Tm(1), two equivalent Tm(2), two equivalent Tm(3), and four equivalent Tm(4) atoms to form a mixture of distorted face, corner, and edge-sharing TmTm10Mg2 cuboctahedra. In the third Tm site, Tm(3) is bonded in a 6-coordinate geometry to two equivalent Mg(2), four equivalent Mg(1), two equivalent Tm(2), and two equivalent Tm(4) atoms. In the fourth Tm site, Tm(4) is bonded to two equivalent Mg(2), two equivalent Tm(1), two equivalent Tm(3), two equivalent Tm(4), and four equivalent Tm(2) atoms to form a mixture of distorted face, corner, and edge-sharing TmTm10Mg2 cuboctahedra. is represented by the CIF file [CIF]
data_Tm2Mg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.632
_cell_length_b   8.656
_cell_length_c   5.364
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   77.876
_symmetry_Int_Tables_number   1
_cell_volume   164.878
_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
  Tm  Tm0  1  0.982  0.037  1.000  1.0
  Tm  Tm1  1  0.660  0.678  0.000  1.0
  Tm  Tm2  1  0.796  0.408  0.500  1.0
  Tm  Tm3  1  0.116  0.767  0.500  1.0
  Mg  Mg4  1  0.322  0.355  0.000  1.0
  Mg  Mg5  1  0.458  0.089  0.500  1.0
[/CIF]
.
The crystal structure described by Tm2Mg 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 Tm(1), two equivalent Tm(2), and four equivalent Tm(3) atoms. In the second Mg site, Mg(2) is bonded in a distorted body-centered cubic geometry to two equivalent Tm(3), two equivalent Tm(4), and four equivalent Tm(1) atoms. There are four inequivalent Tm sites. In the first Tm site, Tm(1) is bonded in a 6-coordinate geometry to two equivalent Mg(1), four equivalent Mg(2), two equivalent Tm(2), and two equivalent Tm(4) atoms. In the second Tm site, Tm(2) is bonded to two equivalent Mg(1), two equivalent Tm(1), two equivalent Tm(2), two equivalent Tm(3), and four equivalent Tm(4) atoms to form a mixture of distorted face, corner, and edge-sharing TmTm10Mg2 cuboctahedra. In the third Tm site, Tm(3) is bonded in a 6-coordinate geometry to two equivalent Mg(2), four equivalent Mg(1), two equivalent Tm(2), and two equivalent Tm(4) atoms. In the fourth Tm site, Tm(4) is bonded to two equivalent Mg(2), two equivalent Tm(1), two equivalent Tm(3), two equivalent Tm(4), and four equivalent Tm(2) atoms to form a mixture of distorted face, corner, and edge-sharing TmTm10Mg2 cuboctahedra. is represented by the CIF file [CIF]
data_Tm2Mg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.632
_cell_length_b   8.656
_cell_length_c   5.364
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   77.876
_symmetry_Int_Tables_number   1
_cell_volume   164.878
_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
  Tm  Tm0  1  0.982  0.037  1.000  1.0
  Tm  Tm1  1  0.660  0.678  0.000  1.0
  Tm  Tm2  1  0.796  0.408  0.500  1.0
  Tm  Tm3  1  0.116  0.767  0.500  1.0
  Mg  Mg4  1  0.322  0.355  0.000  1.0
  Mg  Mg5  1  0.458  0.089  0.500  1.0
[/CIF]
.