data_CuTcAs
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.05
_cell_length_b   4.05
_cell_length_c   4.05
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   CuTcAs
_chemical_formula_sum   'Cu1 Tc1 As1'
_cell_volume   46.88
_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
  Cu  Cu1  1  0.0  0.0  0.0  1.0
  Tc  Tc2  1  0.86  0.86  0.86  1.0
  As  As0  1  0.43  0.43  0.43  1.0

data_CuTcAs
_symmetry_space_group_name_H-M   R3m
_cell_length_a   4.05
_cell_length_b   4.05
_cell_length_c   9.91
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   CuTcAs
_chemical_formula_sum   'Cu3 Tc3 As3'
_cell_volume   140.63
_cell_formula_units_Z   3
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  '-y, x-y, z'
  3  '-x+y, -x, z'
  4  '-y, -x, z'
  5  '-x+y, y, z'
  6  'x, x-y, z'
  7  'x+1/3, y+2/3, z+2/3'
  8  '-y+1/3, x-y+2/3, z+2/3'
  9  '-x+y+1/3, -x+2/3, z+2/3'
  10  '-y+1/3, -x+2/3, z+2/3'
  11  '-x+y+1/3, y+2/3, z+2/3'
  12  'x+1/3, x-y+2/3, z+2/3'
  13  'x+2/3, y+1/3, z+1/3'
  14  '-y+2/3, x-y+1/3, z+1/3'
  15  '-x+y+2/3, -x+1/3, z+1/3'
  16  '-y+2/3, -x+1/3, z+1/3'
  17  '-x+y+2/3, y+1/3, z+1/3'
  18  'x+2/3, x-y+1/3, z+1/3'
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
  Cu  Cu0  3  0.0  0.0  0.0  1.0
  Tc  Tc1  3  0.0  0.0  0.14  1.0
  As  As2  3  0.0  0.0  0.57  1.0

Cu Tc As
TcCuAs crystallizes in the trigonal R3m space group. Tc(1) is bonded to one Cu(1) and three equivalent As(1) atoms to form TcCuAs3 tetrahedra that share corners with three equivalent Cu(1)TcAs3 tetrahedra, corners with six equivalent Tc(1)CuAs3 tetrahedra, and edges with three equivalent Cu(1)TcAs3 tetrahedra. The Tc(1)-Cu(1) bond length is 1.37 Å. All Tc(1)-As(1) bond lengths are 2.53 Å. Cu(1) is bonded to one Tc(1) and three equivalent As(1) atoms to form CuTcAs3 tetrahedra that share corners with three equivalent Tc(1)CuAs3 tetrahedra, corners with six equivalent Cu(1)TcAs3 tetrahedra, and edges with three equivalent Tc(1)CuAs3 tetrahedra. All Cu(1)-As(1) bond lengths are 2.53 Å. As(1) is bonded in a 6-coordinate geometry to three equivalent Tc(1) and three equivalent Cu(1) atoms.