The compound described by TmMn2Si2 crystallizes in the tetragonal I4/mmm space group. Tm(1) is bonded in a 8-coordinate geometry to eight equivalent Si(1) atoms. Mn(1) is bonded to four equivalent Si(1) atoms to form a mixture of corner and edge-sharing MnSi4 tetrahedra. Si(1) is bonded in a 9-coordinate geometry to four equivalent Tm(1), four equivalent Mn(1), and one Si(1) atom. is represented by the CIF file [CIF]
data_Tm(MnSi)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.869
_cell_length_b   5.869
_cell_length_c   5.869
_cell_angle_alpha   141.764
_cell_angle_beta   141.764
_cell_angle_gamma   55.185
_symmetry_Int_Tables_number   1
_cell_volume   76.883
_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  0.000  0.000  0.000  1.0
  Mn  Mn1  1  0.750  0.250  0.500  1.0
  Mn  Mn2  1  0.250  0.750  0.500  1.0
  Si  Si3  1  0.384  0.384  0.000  1.0
  Si  Si4  1  0.616  0.616  0.000  1.0
[/CIF]
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The compound described by TmMn2Si2 crystallizes in the tetragonal I4/mmm space group. Tm(1) is bonded in a 8-coordinate geometry to eight equivalent Si(1) atoms. Mn(1) is bonded to four equivalent Si(1) atoms to form a mixture of corner and edge-sharing MnSi4 tetrahedra. Si(1) is bonded in a 9-coordinate geometry to four equivalent Tm(1), four equivalent Mn(1), and one Si(1) atom. is represented by the CIF file [CIF]
data_Tm(MnSi)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.869
_cell_length_b   5.869
_cell_length_c   5.869
_cell_angle_alpha   141.764
_cell_angle_beta   141.764
_cell_angle_gamma   55.185
_symmetry_Int_Tables_number   1
_cell_volume   76.883
_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  0.000  0.000  0.000  1.0
  Mn  Mn1  1  0.750  0.250  0.500  1.0
  Mn  Mn2  1  0.250  0.750  0.500  1.0
  Si  Si3  1  0.384  0.384  0.000  1.0
  Si  Si4  1  0.616  0.616  0.000  1.0
[/CIF]
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