The compound described by Tm8CoGa3 crystallizes in the hexagonal P6_3mc space group. There are four inequivalent Tm sites. In the first Tm site, Tm(1) is bonded to one Co(1) and four equivalent Ga(1) atoms to form distorted TmGa4Co trigonal pyramids that share corners with two equivalent Tm(4)Ga6 octahedra, corners with three equivalent Tm(2)Ga3Co tetrahedra, corners with six equivalent Tm(1)Ga4Co trigonal pyramids,  an edgeedge with one Tm(2)Ga3Co tetrahedra, edges with four equivalent Tm(1)Ga4Co trigonal pyramids, and faces with two equivalent Tm(4)Ga6 octahedra. The corner-sharing octahedral tilt angles range from 53-58°. In the second Tm site, Tm(2) is bonded to one Co(1) and three equivalent Ga(1) atoms to form distorted TmGa3Co tetrahedra that share corners with six equivalent Tm(4)Ga6 octahedra, corners with nine equivalent Tm(1)Ga4Co trigonal pyramids, and edges with three equivalent Tm(1)Ga4Co trigonal pyramids. The corner-sharing octahedral tilt angles range from 17-46°. In the third Tm site, Tm(3) is bonded in a 3-coordinate geometry to one Co(1) and four equivalent Ga(1) atoms. In the fourth Tm site, Tm(4) is bonded to six equivalent Ga(1) atoms to form distorted TmGa6 octahedra that share corners with six equivalent Tm(2)Ga3Co tetrahedra, corners with six equivalent Tm(1)Ga4Co trigonal pyramids, faces with two equivalent Tm(4)Ga6 octahedra, and faces with six equivalent Tm(1)Ga4Co trigonal pyramids. Co(1) is bonded in a 7-coordinate geometry to one Tm(2), three equivalent Tm(1), and three equivalent Tm(3) atoms. Ga(1) is bonded in a 11-coordinate geometry to one Tm(2), two equivalent Tm(4), four equivalent Tm(1), and four equivalent Tm(3) atoms. is represented by the CIF file [CIF]
data_Tm8Ga3Co
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.792
_cell_length_b   9.792
_cell_length_c   6.813
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   565.720
_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  0.173  0.827  0.990  1.0
  Tm  Tm1  1  0.347  0.173  0.490  1.0
  Tm  Tm2  1  0.827  0.653  0.490  1.0
  Tm  Tm3  1  0.173  0.347  0.990  1.0
  Tm  Tm4  1  0.653  0.827  0.990  1.0
  Tm  Tm5  1  0.827  0.173  0.490  1.0
  Tm  Tm6  1  0.333  0.667  0.671  1.0
  Tm  Tm7  1  0.667  0.333  0.171  1.0
  Tm  Tm8  1  0.463  0.537  0.291  1.0
  Tm  Tm9  1  0.927  0.463  0.791  1.0
  Tm  Tm10  1  0.537  0.073  0.791  1.0
  Tm  Tm11  1  0.463  0.927  0.291  1.0
  Tm  Tm12  1  0.073  0.537  0.291  1.0
  Tm  Tm13  1  0.537  0.463  0.791  1.0
  Tm  Tm14  1  0.000  1.000  0.269  1.0
  Tm  Tm15  1  0.000  0.000  0.769  1.0
  Ga  Ga16  1  0.164  0.836  0.541  1.0
  Ga  Ga17  1  0.327  0.164  0.041  1.0
  Ga  Ga18  1  0.836  0.673  0.041  1.0
  Ga  Ga19  1  0.164  0.327  0.541  1.0
  Ga  Ga20  1  0.673  0.836  0.541  1.0
  Ga  Ga21  1  0.836  0.164  0.041  1.0
  Co  Co22  1  0.333  0.667  0.057  1.0
  Co  Co23  1  0.667  0.333  0.557  1.0
[/CIF]
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The compound described by Tm8CoGa3 crystallizes in the hexagonal P6_3mc space group. There are four inequivalent Tm sites. In the first Tm site, Tm(1) is bonded to one Co(1) and four equivalent Ga(1) atoms to form distorted TmGa4Co trigonal pyramids that share corners with two equivalent Tm(4)Ga6 octahedra, corners with three equivalent Tm(2)Ga3Co tetrahedra, corners with six equivalent Tm(1)Ga4Co trigonal pyramids,  an edgeedge with one Tm(2)Ga3Co tetrahedra, edges with four equivalent Tm(1)Ga4Co trigonal pyramids, and faces with two equivalent Tm(4)Ga6 octahedra. The corner-sharing octahedral tilt angles range from 53-58°. In the second Tm site, Tm(2) is bonded to one Co(1) and three equivalent Ga(1) atoms to form distorted TmGa3Co tetrahedra that share corners with six equivalent Tm(4)Ga6 octahedra, corners with nine equivalent Tm(1)Ga4Co trigonal pyramids, and edges with three equivalent Tm(1)Ga4Co trigonal pyramids. The corner-sharing octahedral tilt angles range from 17-46°. In the third Tm site, Tm(3) is bonded in a 3-coordinate geometry to one Co(1) and four equivalent Ga(1) atoms. In the fourth Tm site, Tm(4) is bonded to six equivalent Ga(1) atoms to form distorted TmGa6 octahedra that share corners with six equivalent Tm(2)Ga3Co tetrahedra, corners with six equivalent Tm(1)Ga4Co trigonal pyramids, faces with two equivalent Tm(4)Ga6 octahedra, and faces with six equivalent Tm(1)Ga4Co trigonal pyramids. Co(1) is bonded in a 7-coordinate geometry to one Tm(2), three equivalent Tm(1), and three equivalent Tm(3) atoms. Ga(1) is bonded in a 11-coordinate geometry to one Tm(2), two equivalent Tm(4), four equivalent Tm(1), and four equivalent Tm(3) atoms. is represented by the CIF file [CIF]
data_Tm8Ga3Co
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.792
_cell_length_b   9.792
_cell_length_c   6.813
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   565.720
_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  0.173  0.827  0.990  1.0
  Tm  Tm1  1  0.347  0.173  0.490  1.0
  Tm  Tm2  1  0.827  0.653  0.490  1.0
  Tm  Tm3  1  0.173  0.347  0.990  1.0
  Tm  Tm4  1  0.653  0.827  0.990  1.0
  Tm  Tm5  1  0.827  0.173  0.490  1.0
  Tm  Tm6  1  0.333  0.667  0.671  1.0
  Tm  Tm7  1  0.667  0.333  0.171  1.0
  Tm  Tm8  1  0.463  0.537  0.291  1.0
  Tm  Tm9  1  0.927  0.463  0.791  1.0
  Tm  Tm10  1  0.537  0.073  0.791  1.0
  Tm  Tm11  1  0.463  0.927  0.291  1.0
  Tm  Tm12  1  0.073  0.537  0.291  1.0
  Tm  Tm13  1  0.537  0.463  0.791  1.0
  Tm  Tm14  1  0.000  1.000  0.269  1.0
  Tm  Tm15  1  0.000  0.000  0.769  1.0
  Ga  Ga16  1  0.164  0.836  0.541  1.0
  Ga  Ga17  1  0.327  0.164  0.041  1.0
  Ga  Ga18  1  0.836  0.673  0.041  1.0
  Ga  Ga19  1  0.164  0.327  0.541  1.0
  Ga  Ga20  1  0.673  0.836  0.541  1.0
  Ga  Ga21  1  0.836  0.164  0.041  1.0
  Co  Co22  1  0.333  0.667  0.057  1.0
  Co  Co23  1  0.667  0.333  0.557  1.0
[/CIF]
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