The crystal structure described by TcAl4 crystallizes in the monoclinic Cm space group. There are two inequivalent Tc sites. In the first Tc site, Tc(1) is bonded in a 10-coordinate geometry to two equivalent Al(1), two equivalent Al(2), two equivalent Al(3), two equivalent Al(4), and two equivalent Al(5) atoms. In the second Tc site, Tc(2) is bonded in a 11-coordinate geometry to one Al(1), one Al(2), one Al(3), two equivalent Al(4), two equivalent Al(5), two equivalent Al(6), and two equivalent Al(7) atoms. There are seven inequivalent Al sites. In the first Al site, Al(1) is bonded in a 11-coordinate geometry to two equivalent Tc(1), two equivalent Tc(2), one Al(2), two equivalent Al(3), two equivalent Al(4), and two equivalent Al(5) atoms. In the second Al site, Al(2) is bonded in a 13-coordinate geometry to two equivalent Tc(1), two equivalent Tc(2), one Al(1), two equivalent Al(4), two equivalent Al(5), and four equivalent Al(3) atoms. In the third Al site, Al(3) is bonded in a distorted linear geometry to one Tc(1), one Tc(2), one Al(1), one Al(6), and two equivalent Al(2) atoms. In the fourth Al site, Al(4) is bonded in a 3-coordinate geometry to one Tc(1), two equivalent Tc(2), one Al(1), one Al(2), one Al(6), and two equivalent Al(7) atoms. In the fifth Al site, Al(5) is bonded in a 3-coordinate geometry to one Tc(1), two equivalent Tc(2), one Al(1), one Al(2), one Al(6), and two equivalent Al(7) atoms. In the sixth Al site, Al(6) is bonded in a 10-coordinate geometry to two equivalent Tc(2), one Al(3), one Al(4), one Al(5), two equivalent Al(6), and three equivalent Al(7) atoms. In the seventh Al site, Al(7) is bonded in a 11-coordinate geometry to two equivalent Tc(2), two equivalent Al(4), two equivalent Al(5), two equivalent Al(7), and three equivalent Al(6) atoms. is represented by the CIF card [CIF]
data_Al4Tc
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.161
_cell_length_b   5.105
_cell_length_c   9.113
_cell_angle_alpha   87.031
_cell_angle_beta   73.551
_cell_angle_gamma   79.462
_symmetry_Int_Tables_number   1
_cell_volume   226.379
_cell_formula_units_Z   3
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
  Al  Al0  1  0.849  0.510  0.000  1.0
  Al  Al1  1  0.505  0.147  0.000  1.0
  Al  Al2  1  0.271  0.686  0.152  1.0
  Al  Al3  1  0.423  0.686  0.848  1.0
  Al  Al4  1  0.057  0.220  0.238  1.0
  Al  Al5  1  0.296  0.220  0.762  1.0
  Al  Al6  1  0.955  0.807  0.748  1.0
  Al  Al7  1  0.703  0.807  0.252  1.0
  Al  Al8  1  0.075  0.586  0.465  1.0
  Al  Al9  1  0.540  0.586  0.535  1.0
  Al  Al10  1  0.230  0.068  0.496  1.0
  Al  Al11  1  0.726  0.068  0.504  1.0
  Tc  Tc12  1  0.012  0.995  0.000  1.0
  Tc  Tc13  1  0.805  0.330  0.725  1.0
  Tc  Tc14  1  0.529  0.330  0.275  1.0
[/CIF]
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The crystal structure described by TcAl4 crystallizes in the monoclinic Cm space group. There are two inequivalent Tc sites. In the first Tc site, Tc(1) is bonded in a 10-coordinate geometry to two equivalent Al(1), two equivalent Al(2), two equivalent Al(3), two equivalent Al(4), and two equivalent Al(5) atoms. In the second Tc site, Tc(2) is bonded in a 11-coordinate geometry to one Al(1), one Al(2), one Al(3), two equivalent Al(4), two equivalent Al(5), two equivalent Al(6), and two equivalent Al(7) atoms. There are seven inequivalent Al sites. In the first Al site, Al(1) is bonded in a 11-coordinate geometry to two equivalent Tc(1), two equivalent Tc(2), one Al(2), two equivalent Al(3), two equivalent Al(4), and two equivalent Al(5) atoms. In the second Al site, Al(2) is bonded in a 13-coordinate geometry to two equivalent Tc(1), two equivalent Tc(2), one Al(1), two equivalent Al(4), two equivalent Al(5), and four equivalent Al(3) atoms. In the third Al site, Al(3) is bonded in a distorted linear geometry to one Tc(1), one Tc(2), one Al(1), one Al(6), and two equivalent Al(2) atoms. In the fourth Al site, Al(4) is bonded in a 3-coordinate geometry to one Tc(1), two equivalent Tc(2), one Al(1), one Al(2), one Al(6), and two equivalent Al(7) atoms. In the fifth Al site, Al(5) is bonded in a 3-coordinate geometry to one Tc(1), two equivalent Tc(2), one Al(1), one Al(2), one Al(6), and two equivalent Al(7) atoms. In the sixth Al site, Al(6) is bonded in a 10-coordinate geometry to two equivalent Tc(2), one Al(3), one Al(4), one Al(5), two equivalent Al(6), and three equivalent Al(7) atoms. In the seventh Al site, Al(7) is bonded in a 11-coordinate geometry to two equivalent Tc(2), two equivalent Al(4), two equivalent Al(5), two equivalent Al(7), and three equivalent Al(6) atoms. is represented by the CIF card [CIF]
data_Al4Tc
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.161
_cell_length_b   5.105
_cell_length_c   9.113
_cell_angle_alpha   87.031
_cell_angle_beta   73.551
_cell_angle_gamma   79.462
_symmetry_Int_Tables_number   1
_cell_volume   226.379
_cell_formula_units_Z   3
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
  Al  Al0  1  0.849  0.510  0.000  1.0
  Al  Al1  1  0.505  0.147  0.000  1.0
  Al  Al2  1  0.271  0.686  0.152  1.0
  Al  Al3  1  0.423  0.686  0.848  1.0
  Al  Al4  1  0.057  0.220  0.238  1.0
  Al  Al5  1  0.296  0.220  0.762  1.0
  Al  Al6  1  0.955  0.807  0.748  1.0
  Al  Al7  1  0.703  0.807  0.252  1.0
  Al  Al8  1  0.075  0.586  0.465  1.0
  Al  Al9  1  0.540  0.586  0.535  1.0
  Al  Al10  1  0.230  0.068  0.496  1.0
  Al  Al11  1  0.726  0.068  0.504  1.0
  Tc  Tc12  1  0.012  0.995  0.000  1.0
  Tc  Tc13  1  0.805  0.330  0.725  1.0
  Tc  Tc14  1  0.529  0.330  0.275  1.0
[/CIF]
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