The material structure described by Tc2As3 crystallizes in the triclinic P-1 space group. There are four inequivalent Tc sites. In the first Tc site, Tc(1) is bonded in a 6-coordinate geometry to one As(1), one As(2), one As(3), one As(5), and two equivalent As(6) atoms. In the second Tc site, Tc(2) is bonded to one As(1), one As(2), one As(4), one As(6), and two equivalent As(5) atoms to form a mixture of distorted corner, edge, and face-sharing TcAs6 octahedra. The corner-sharing octahedral tilt angles range from 40-59°. In the third Tc site, Tc(3) is bonded to one As(1), one As(2), one As(3), one As(5), and two equivalent As(4) atoms to form a mixture of distorted corner, edge, and face-sharing TcAs6 octahedra. The corner-sharing octahedral tilt angles range from 41-56°. In the fourth Tc site, Tc(4) is bonded to one As(1), one As(2), one As(4), one As(6), and two equivalent As(3) atoms to form a mixture of distorted corner and edge-sharing TcAs6 octahedra. The corner-sharing octahedral tilt angles range from 40-59°. There are six inequivalent As sites. In the first As site, As(1) is bonded in a 5-coordinate geometry to one Tc(1), one Tc(2), one Tc(3), one Tc(4), and one As(2) atom. In the second As site, As(2) is bonded in a 5-coordinate geometry to one Tc(1), one Tc(2), one Tc(3), one Tc(4), and one As(1) atom. In the third As site, As(3) is bonded in a distorted rectangular see-saw-like geometry to one Tc(1), one Tc(3), and two equivalent Tc(4) atoms. In the fourth As site, As(4) is bonded in a 4-coordinate geometry to one Tc(2), one Tc(4), and two equivalent Tc(3) atoms. In the fifth As site, As(5) is bonded in a 5-coordinate geometry to one Tc(1), one Tc(3), two equivalent Tc(2), and one As(5) atom. In the sixth As site, As(6) is bonded in a 5-coordinate geometry to one Tc(2), one Tc(4), two equivalent Tc(1), and one As(6) atom. is represented by the CIF file [CIF]
data_Tc2As3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.650
_cell_length_b   6.638
_cell_length_c   8.004
_cell_angle_alpha   95.517
_cell_angle_beta   101.699
_cell_angle_gamma   104.560
_symmetry_Int_Tables_number   1
_cell_volume   330.805
_cell_formula_units_Z   4
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  0.914  0.424  0.143  1.0
  Tc  Tc1  1  0.086  0.576  0.857  1.0
  Tc  Tc2  1  0.369  0.427  0.134  1.0
  Tc  Tc3  1  0.631  0.573  0.866  1.0
  Tc  Tc4  1  0.530  0.863  0.365  1.0
  Tc  Tc5  1  0.470  0.137  0.635  1.0
  Tc  Tc6  1  0.089  0.874  0.375  1.0
  Tc  Tc7  1  0.911  0.126  0.625  1.0
  As  As8  1  0.737  0.592  0.348  1.0
  As  As9  1  0.263  0.408  0.652  1.0
  As  As10  1  0.236  0.565  0.384  1.0
  As  As11  1  0.764  0.435  0.616  1.0
  As  As12  1  0.859  0.126  0.315  1.0
  As  As13  1  0.141  0.874  0.685  1.0
  As  As14  1  0.372  0.153  0.321  1.0
  As  As15  1  0.628  0.847  0.679  1.0
  As  As16  1  0.545  0.206  0.964  1.0
  As  As17  1  0.455  0.794  0.036  1.0
  As  As18  1  0.033  0.191  0.951  1.0
  As  As19  1  0.967  0.809  0.049  1.0
[/CIF]
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The material structure described by Tc2As3 crystallizes in the triclinic P-1 space group. There are four inequivalent Tc sites. In the first Tc site, Tc(1) is bonded in a 6-coordinate geometry to one As(1), one As(2), one As(3), one As(5), and two equivalent As(6) atoms. In the second Tc site, Tc(2) is bonded to one As(1), one As(2), one As(4), one As(6), and two equivalent As(5) atoms to form a mixture of distorted corner, edge, and face-sharing TcAs6 octahedra. The corner-sharing octahedral tilt angles range from 40-59°. In the third Tc site, Tc(3) is bonded to one As(1), one As(2), one As(3), one As(5), and two equivalent As(4) atoms to form a mixture of distorted corner, edge, and face-sharing TcAs6 octahedra. The corner-sharing octahedral tilt angles range from 41-56°. In the fourth Tc site, Tc(4) is bonded to one As(1), one As(2), one As(4), one As(6), and two equivalent As(3) atoms to form a mixture of distorted corner and edge-sharing TcAs6 octahedra. The corner-sharing octahedral tilt angles range from 40-59°. There are six inequivalent As sites. In the first As site, As(1) is bonded in a 5-coordinate geometry to one Tc(1), one Tc(2), one Tc(3), one Tc(4), and one As(2) atom. In the second As site, As(2) is bonded in a 5-coordinate geometry to one Tc(1), one Tc(2), one Tc(3), one Tc(4), and one As(1) atom. In the third As site, As(3) is bonded in a distorted rectangular see-saw-like geometry to one Tc(1), one Tc(3), and two equivalent Tc(4) atoms. In the fourth As site, As(4) is bonded in a 4-coordinate geometry to one Tc(2), one Tc(4), and two equivalent Tc(3) atoms. In the fifth As site, As(5) is bonded in a 5-coordinate geometry to one Tc(1), one Tc(3), two equivalent Tc(2), and one As(5) atom. In the sixth As site, As(6) is bonded in a 5-coordinate geometry to one Tc(2), one Tc(4), two equivalent Tc(1), and one As(6) atom. is represented by the CIF file [CIF]
data_Tc2As3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.650
_cell_length_b   6.638
_cell_length_c   8.004
_cell_angle_alpha   95.517
_cell_angle_beta   101.699
_cell_angle_gamma   104.560
_symmetry_Int_Tables_number   1
_cell_volume   330.805
_cell_formula_units_Z   4
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  0.914  0.424  0.143  1.0
  Tc  Tc1  1  0.086  0.576  0.857  1.0
  Tc  Tc2  1  0.369  0.427  0.134  1.0
  Tc  Tc3  1  0.631  0.573  0.866  1.0
  Tc  Tc4  1  0.530  0.863  0.365  1.0
  Tc  Tc5  1  0.470  0.137  0.635  1.0
  Tc  Tc6  1  0.089  0.874  0.375  1.0
  Tc  Tc7  1  0.911  0.126  0.625  1.0
  As  As8  1  0.737  0.592  0.348  1.0
  As  As9  1  0.263  0.408  0.652  1.0
  As  As10  1  0.236  0.565  0.384  1.0
  As  As11  1  0.764  0.435  0.616  1.0
  As  As12  1  0.859  0.126  0.315  1.0
  As  As13  1  0.141  0.874  0.685  1.0
  As  As14  1  0.372  0.153  0.321  1.0
  As  As15  1  0.628  0.847  0.679  1.0
  As  As16  1  0.545  0.206  0.964  1.0
  As  As17  1  0.455  0.794  0.036  1.0
  As  As18  1  0.033  0.191  0.951  1.0
  As  As19  1  0.967  0.809  0.049  1.0
[/CIF]
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