The compound described by Tb2PtAl6Si4 crystallizes in the trigonal R-3m space group. Tb(1) is bonded to three equivalent Si(1) and three equivalent Si(2) atoms to form TbSi6 octahedra that share corners with three equivalent Al(1)Si3Pt tetrahedra, corners with three equivalent Al(3)SiPt3 tetrahedra, corners with six equivalent Al(2)Si4 tetrahedra, edges with six equivalent Tb(1)Si6 octahedra, edges with three equivalent Al(1)Si3Pt tetrahedra, and edges with three equivalent Al(2)Si4 tetrahedra. Pt(1) is bonded in a body-centered cubic geometry to two equivalent Al(1) and six equivalent Al(3) atoms. There are three inequivalent Al sites. In the first Al site, Al(1) is bonded to one Pt(1) and three equivalent Si(1) atoms to form AlSi3Pt tetrahedra that share corners with three equivalent Tb(1)Si6 octahedra, corners with three equivalent Al(3)SiPt3 tetrahedra, corners with seven equivalent Al(1)Si3Pt tetrahedra, edges with three equivalent Tb(1)Si6 octahedra, and edges with three equivalent Al(3)SiPt3 tetrahedra. The corner-sharing octahedral tilt angles are 15°. In the second Al site, Al(2) is bonded to four equivalent Si(2) atoms to form AlSi4 tetrahedra that share corners with six equivalent Tb(1)Si6 octahedra, corners with six equivalent Al(2)Si4 tetrahedra, edges with three equivalent Tb(1)Si6 octahedra, and edges with three equivalent Al(2)Si4 tetrahedra. The corner-sharing octahedral tilt angles range from 21-53°. In the third Al site, Al(3) is bonded to three equivalent Pt(1) and one Si(1) atom to form distorted AlSiPt3 tetrahedra that share corners with three equivalent Tb(1)Si6 octahedra, corners with three equivalent Al(1)Si3Pt tetrahedra, corners with nine equivalent Al(3)SiPt3 tetrahedra, edges with three equivalent Al(1)Si3Pt tetrahedra, and edges with three equivalent Al(3)SiPt3 tetrahedra. The corner-sharing octahedral tilt angles are 55°. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to three equivalent Tb(1), one Al(3), and three equivalent Al(1) atoms to form a mixture of distorted edge and corner-sharing SiTb3Al4 pentagonal bipyramids. In the second Si site, Si(2) is bonded to three equivalent Tb(1) and four equivalent Al(2) atoms to form a mixture of distorted edge and corner-sharing SiTb3Al4 pentagonal bipyramids. is represented by the CIF card [CIF]
data_Tb2Al6Si4Pt
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   17.145
_cell_length_b   17.145
_cell_length_c   17.145
_cell_angle_alpha   13.897
_cell_angle_beta   13.897
_cell_angle_gamma   13.897
_symmetry_Int_Tables_number   1
_cell_volume   253.026
_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
  Tb  Tb0  1  0.567  0.567  0.567  1.0
  Tb  Tb1  1  0.433  0.433  0.433  1.0
  Al  Al2  1  0.951  0.951  0.951  1.0
  Al  Al3  1  0.049  0.049  0.049  1.0
  Al  Al4  1  0.185  0.185  0.185  1.0
  Al  Al5  1  0.815  0.815  0.815  1.0
  Al  Al6  1  0.319  0.319  0.319  1.0
  Al  Al7  1  0.681  0.681  0.681  1.0
  Si  Si8  1  0.734  0.734  0.734  1.0
  Si  Si9  1  0.135  0.135  0.135  1.0
  Si  Si10  1  0.266  0.266  0.266  1.0
  Si  Si11  1  0.865  0.865  0.865  1.0
  Pt  Pt12  1  0.000  0.000  0.000  1.0
[/CIF]
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The compound described by Tb2PtAl6Si4 crystallizes in the trigonal R-3m space group. Tb(1) is bonded to three equivalent Si(1) and three equivalent Si(2) atoms to form TbSi6 octahedra that share corners with three equivalent Al(1)Si3Pt tetrahedra, corners with three equivalent Al(3)SiPt3 tetrahedra, corners with six equivalent Al(2)Si4 tetrahedra, edges with six equivalent Tb(1)Si6 octahedra, edges with three equivalent Al(1)Si3Pt tetrahedra, and edges with three equivalent Al(2)Si4 tetrahedra. Pt(1) is bonded in a body-centered cubic geometry to two equivalent Al(1) and six equivalent Al(3) atoms. There are three inequivalent Al sites. In the first Al site, Al(1) is bonded to one Pt(1) and three equivalent Si(1) atoms to form AlSi3Pt tetrahedra that share corners with three equivalent Tb(1)Si6 octahedra, corners with three equivalent Al(3)SiPt3 tetrahedra, corners with seven equivalent Al(1)Si3Pt tetrahedra, edges with three equivalent Tb(1)Si6 octahedra, and edges with three equivalent Al(3)SiPt3 tetrahedra. The corner-sharing octahedral tilt angles are 15°. In the second Al site, Al(2) is bonded to four equivalent Si(2) atoms to form AlSi4 tetrahedra that share corners with six equivalent Tb(1)Si6 octahedra, corners with six equivalent Al(2)Si4 tetrahedra, edges with three equivalent Tb(1)Si6 octahedra, and edges with three equivalent Al(2)Si4 tetrahedra. The corner-sharing octahedral tilt angles range from 21-53°. In the third Al site, Al(3) is bonded to three equivalent Pt(1) and one Si(1) atom to form distorted AlSiPt3 tetrahedra that share corners with three equivalent Tb(1)Si6 octahedra, corners with three equivalent Al(1)Si3Pt tetrahedra, corners with nine equivalent Al(3)SiPt3 tetrahedra, edges with three equivalent Al(1)Si3Pt tetrahedra, and edges with three equivalent Al(3)SiPt3 tetrahedra. The corner-sharing octahedral tilt angles are 55°. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to three equivalent Tb(1), one Al(3), and three equivalent Al(1) atoms to form a mixture of distorted edge and corner-sharing SiTb3Al4 pentagonal bipyramids. In the second Si site, Si(2) is bonded to three equivalent Tb(1) and four equivalent Al(2) atoms to form a mixture of distorted edge and corner-sharing SiTb3Al4 pentagonal bipyramids. is represented by the CIF card [CIF]
data_Tb2Al6Si4Pt
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   17.145
_cell_length_b   17.145
_cell_length_c   17.145
_cell_angle_alpha   13.897
_cell_angle_beta   13.897
_cell_angle_gamma   13.897
_symmetry_Int_Tables_number   1
_cell_volume   253.026
_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
  Tb  Tb0  1  0.567  0.567  0.567  1.0
  Tb  Tb1  1  0.433  0.433  0.433  1.0
  Al  Al2  1  0.951  0.951  0.951  1.0
  Al  Al3  1  0.049  0.049  0.049  1.0
  Al  Al4  1  0.185  0.185  0.185  1.0
  Al  Al5  1  0.815  0.815  0.815  1.0
  Al  Al6  1  0.319  0.319  0.319  1.0
  Al  Al7  1  0.681  0.681  0.681  1.0
  Si  Si8  1  0.734  0.734  0.734  1.0
  Si  Si9  1  0.135  0.135  0.135  1.0
  Si  Si10  1  0.266  0.266  0.266  1.0
  Si  Si11  1  0.865  0.865  0.865  1.0
  Pt  Pt12  1  0.000  0.000  0.000  1.0
[/CIF]
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