The crystal structure described by Mg3Tm is Uranium Silicide structured and crystallizes in the tetragonal P4/mmm space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to eight equivalent Mg(2) and four equivalent Tm(1) atoms to form MgTm4Mg8 cuboctahedra that share corners with twelve equivalent Mg(1)Tm4Mg8 cuboctahedra, edges with eight equivalent Tm(1)Mg12 cuboctahedra, faces with four equivalent Tm(1)Mg12 cuboctahedra, and faces with six equivalent Mg(1)Tm4Mg8 cuboctahedra. In the second Mg site, Mg(2) is bonded in a distorted body-centered cubic geometry to four equivalent Mg(1) and four equivalent Tm(1) atoms. Tm(1) is bonded to four equivalent Mg(1) and eight equivalent Mg(2) atoms to form distorted TmMg12 cuboctahedra that share corners with twelve equivalent Tm(1)Mg12 cuboctahedra, edges with eight equivalent Mg(1)Tm4Mg8 cuboctahedra, faces with four equivalent Mg(1)Tm4Mg8 cuboctahedra, and faces with six equivalent Tm(1)Mg12 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_TmMg3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.934
_cell_length_b   4.934
_cell_length_c   4.012
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   97.660
_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
  Tm  Tm0  1  0.500  0.500  0.000  1.0
  Mg  Mg1  1  0.000  0.000  0.000  1.0
  Mg  Mg2  1  0.500  0.000  0.500  1.0
  Mg  Mg3  1  0.000  0.500  0.500  1.0
[/CIF]
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The crystal structure described by Mg3Tm is Uranium Silicide structured and crystallizes in the tetragonal P4/mmm space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to eight equivalent Mg(2) and four equivalent Tm(1) atoms to form MgTm4Mg8 cuboctahedra that share corners with twelve equivalent Mg(1)Tm4Mg8 cuboctahedra, edges with eight equivalent Tm(1)Mg12 cuboctahedra, faces with four equivalent Tm(1)Mg12 cuboctahedra, and faces with six equivalent Mg(1)Tm4Mg8 cuboctahedra. In the second Mg site, Mg(2) is bonded in a distorted body-centered cubic geometry to four equivalent Mg(1) and four equivalent Tm(1) atoms. Tm(1) is bonded to four equivalent Mg(1) and eight equivalent Mg(2) atoms to form distorted TmMg12 cuboctahedra that share corners with twelve equivalent Tm(1)Mg12 cuboctahedra, edges with eight equivalent Mg(1)Tm4Mg8 cuboctahedra, faces with four equivalent Mg(1)Tm4Mg8 cuboctahedra, and faces with six equivalent Tm(1)Mg12 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_TmMg3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.934
_cell_length_b   4.934
_cell_length_c   4.012
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   97.660
_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
  Tm  Tm0  1  0.500  0.500  0.000  1.0
  Mg  Mg1  1  0.000  0.000  0.000  1.0
  Mg  Mg2  1  0.500  0.000  0.500  1.0
  Mg  Mg3  1  0.000  0.500  0.500  1.0
[/CIF]
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