The compound described by Tc3As is Uranium Silicide-like structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Tc sites. In the first Tc site, Tc(1) is bonded to four equivalent Tc(1), four equivalent Tc(2), and four equivalent As(1) atoms to form TcTc8As4 cuboctahedra that share corners with twelve equivalent Tc(1)Tc8As4 cuboctahedra, edges with eight equivalent Tc(1)Tc8As4 cuboctahedra, edges with eight equivalent As(1)Tc12 cuboctahedra, faces with four equivalent As(1)Tc12 cuboctahedra, and faces with ten equivalent Tc(1)Tc8As4 cuboctahedra. In the second Tc site, Tc(2) is bonded in a distorted square co-planar geometry to eight equivalent Tc(1) and four equivalent As(1) atoms. As(1) is bonded to four equivalent Tc(2) and eight equivalent Tc(1) atoms to form AsTc12 cuboctahedra that share corners with four equivalent As(1)Tc12 cuboctahedra, edges with eight equivalent As(1)Tc12 cuboctahedra, edges with sixteen equivalent Tc(1)Tc8As4 cuboctahedra, faces with four equivalent As(1)Tc12 cuboctahedra, and faces with eight equivalent Tc(1)Tc8As4 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Tc3As
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.922
_cell_length_b   4.922
_cell_length_c   4.922
_cell_angle_alpha   135.128
_cell_angle_beta   135.128
_cell_angle_gamma   65.332
_symmetry_Int_Tables_number   1
_cell_volume   58.477
_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
  Tc  Tc0  1  0.750  0.250  0.500  1.0
  Tc  Tc1  1  0.250  0.750  0.500  1.0
  Tc  Tc2  1  0.500  0.500  0.000  1.0
  As  As3  1  0.000  0.000  0.000  1.0
[/CIF]
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The compound described by Tc3As is Uranium Silicide-like structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Tc sites. In the first Tc site, Tc(1) is bonded to four equivalent Tc(1), four equivalent Tc(2), and four equivalent As(1) atoms to form TcTc8As4 cuboctahedra that share corners with twelve equivalent Tc(1)Tc8As4 cuboctahedra, edges with eight equivalent Tc(1)Tc8As4 cuboctahedra, edges with eight equivalent As(1)Tc12 cuboctahedra, faces with four equivalent As(1)Tc12 cuboctahedra, and faces with ten equivalent Tc(1)Tc8As4 cuboctahedra. In the second Tc site, Tc(2) is bonded in a distorted square co-planar geometry to eight equivalent Tc(1) and four equivalent As(1) atoms. As(1) is bonded to four equivalent Tc(2) and eight equivalent Tc(1) atoms to form AsTc12 cuboctahedra that share corners with four equivalent As(1)Tc12 cuboctahedra, edges with eight equivalent As(1)Tc12 cuboctahedra, edges with sixteen equivalent Tc(1)Tc8As4 cuboctahedra, faces with four equivalent As(1)Tc12 cuboctahedra, and faces with eight equivalent Tc(1)Tc8As4 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Tc3As
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.922
_cell_length_b   4.922
_cell_length_c   4.922
_cell_angle_alpha   135.128
_cell_angle_beta   135.128
_cell_angle_gamma   65.332
_symmetry_Int_Tables_number   1
_cell_volume   58.477
_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
  Tc  Tc0  1  0.750  0.250  0.500  1.0
  Tc  Tc1  1  0.250  0.750  0.500  1.0
  Tc  Tc2  1  0.500  0.500  0.000  1.0
  As  As3  1  0.000  0.000  0.000  1.0
[/CIF]
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