The structure described by Ta2As crystallizes in the orthorhombic Pnnm space group. There are six inequivalent Ta sites. In the first Ta site, Ta(1) is bonded to one As(3), two equivalent As(1), and two equivalent As(2) atoms to form distorted edge-sharing TaAs5 trigonal bipyramids. In the second Ta site, Ta(2) is bonded in a distorted T-shaped geometry to one As(1), one As(2), and one As(3) atom. In the third Ta site, Ta(3) is bonded in a 3-coordinate geometry to one As(1) and two equivalent As(2) atoms. In the fourth Ta site, Ta(4) is bonded in a 4-coordinate geometry to one As(2), one As(3), and two equivalent As(1) atoms. In the fifth Ta site, Ta(5) is bonded in a 4-coordinate geometry to two equivalent As(2) and two equivalent As(3) atoms. In the sixth Ta site, Ta(6) is bonded in a 4-coordinate geometry to one As(2), two equivalent As(1), and two equivalent As(3) atoms. There are three inequivalent As sites. In the first As site, As(1) is bonded in a 8-coordinate geometry to one Ta(2), one Ta(3), two equivalent Ta(1), two equivalent Ta(4), and two equivalent Ta(6) atoms. In the second As site, As(2) is bonded in a 9-coordinate geometry to one Ta(2), one Ta(4), one Ta(6), two equivalent Ta(1), two equivalent Ta(3), and two equivalent Ta(5) atoms. In the third As site, As(3) is bonded to one Ta(1), one Ta(2), one Ta(4), two equivalent Ta(5), and two equivalent Ta(6) atoms to form distorted edge-sharing AsTa7 pentagonal bipyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ta2As
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.478
_cell_length_b   11.900
_cell_length_c   14.814
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   613.114
_cell_formula_units_Z   12
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
  Ta  Ta0  1  0.000  0.192  0.297  1.0
  Ta  Ta1  1  0.000  0.527  0.110  1.0
  Ta  Ta2  1  0.500  0.913  0.079  1.0
  Ta  Ta3  1  0.000  0.886  0.928  1.0
  Ta  Ta4  1  0.000  0.859  0.477  1.0
  Ta  Ta5  1  0.500  0.692  0.203  1.0
  Ta  Ta6  1  0.500  0.386  0.572  1.0
  Ta  Ta7  1  0.000  0.587  0.579  1.0
  Ta  Ta8  1  0.500  0.614  0.428  1.0
  Ta  Ta9  1  0.000  0.082  0.757  1.0
  Ta  Ta10  1  0.500  0.641  0.977  1.0
  Ta  Ta11  1  0.000  0.141  0.523  1.0
  Ta  Ta12  1  0.000  0.413  0.421  1.0
  Ta  Ta13  1  0.500  0.418  0.257  1.0
  Ta  Ta14  1  0.500  0.582  0.743  1.0
  Ta  Ta15  1  0.500  0.973  0.610  1.0
  Ta  Ta16  1  0.500  0.359  0.023  1.0
  Ta  Ta17  1  0.000  0.114  0.072  1.0
  Ta  Ta18  1  0.500  0.087  0.921  1.0
  Ta  Ta19  1  0.000  0.473  0.890  1.0
  Ta  Ta20  1  0.000  0.808  0.703  1.0
  Ta  Ta21  1  0.500  0.308  0.797  1.0
  Ta  Ta22  1  0.000  0.918  0.243  1.0
  Ta  Ta23  1  0.500  0.027  0.390  1.0
  As  As24  1  0.000  0.423  0.704  1.0
  As  As25  1  0.000  0.248  0.919  1.0
  As  As26  1  0.000  0.311  0.151  1.0
  As  As27  1  0.500  0.748  0.581  1.0
  As  As28  1  0.500  0.252  0.419  1.0
  As  As29  1  0.000  0.577  0.296  1.0
  As  As30  1  0.500  0.189  0.651  1.0
  As  As31  1  0.000  0.752  0.081  1.0
  As  As32  1  0.500  0.811  0.349  1.0
  As  As33  1  0.000  0.689  0.849  1.0
  As  As34  1  0.500  0.077  0.204  1.0
  As  As35  1  0.500  0.923  0.796  1.0
[/CIF]
.
The structure described by Ta2As crystallizes in the orthorhombic Pnnm space group. There are six inequivalent Ta sites. In the first Ta site, Ta(1) is bonded to one As(3), two equivalent As(1), and two equivalent As(2) atoms to form distorted edge-sharing TaAs5 trigonal bipyramids. In the second Ta site, Ta(2) is bonded in a distorted T-shaped geometry to one As(1), one As(2), and one As(3) atom. In the third Ta site, Ta(3) is bonded in a 3-coordinate geometry to one As(1) and two equivalent As(2) atoms. In the fourth Ta site, Ta(4) is bonded in a 4-coordinate geometry to one As(2), one As(3), and two equivalent As(1) atoms. In the fifth Ta site, Ta(5) is bonded in a 4-coordinate geometry to two equivalent As(2) and two equivalent As(3) atoms. In the sixth Ta site, Ta(6) is bonded in a 4-coordinate geometry to one As(2), two equivalent As(1), and two equivalent As(3) atoms. There are three inequivalent As sites. In the first As site, As(1) is bonded in a 8-coordinate geometry to one Ta(2), one Ta(3), two equivalent Ta(1), two equivalent Ta(4), and two equivalent Ta(6) atoms. In the second As site, As(2) is bonded in a 9-coordinate geometry to one Ta(2), one Ta(4), one Ta(6), two equivalent Ta(1), two equivalent Ta(3), and two equivalent Ta(5) atoms. In the third As site, As(3) is bonded to one Ta(1), one Ta(2), one Ta(4), two equivalent Ta(5), and two equivalent Ta(6) atoms to form distorted edge-sharing AsTa7 pentagonal bipyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ta2As
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.478
_cell_length_b   11.900
_cell_length_c   14.814
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   613.114
_cell_formula_units_Z   12
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
  Ta  Ta0  1  0.000  0.192  0.297  1.0
  Ta  Ta1  1  0.000  0.527  0.110  1.0
  Ta  Ta2  1  0.500  0.913  0.079  1.0
  Ta  Ta3  1  0.000  0.886  0.928  1.0
  Ta  Ta4  1  0.000  0.859  0.477  1.0
  Ta  Ta5  1  0.500  0.692  0.203  1.0
  Ta  Ta6  1  0.500  0.386  0.572  1.0
  Ta  Ta7  1  0.000  0.587  0.579  1.0
  Ta  Ta8  1  0.500  0.614  0.428  1.0
  Ta  Ta9  1  0.000  0.082  0.757  1.0
  Ta  Ta10  1  0.500  0.641  0.977  1.0
  Ta  Ta11  1  0.000  0.141  0.523  1.0
  Ta  Ta12  1  0.000  0.413  0.421  1.0
  Ta  Ta13  1  0.500  0.418  0.257  1.0
  Ta  Ta14  1  0.500  0.582  0.743  1.0
  Ta  Ta15  1  0.500  0.973  0.610  1.0
  Ta  Ta16  1  0.500  0.359  0.023  1.0
  Ta  Ta17  1  0.000  0.114  0.072  1.0
  Ta  Ta18  1  0.500  0.087  0.921  1.0
  Ta  Ta19  1  0.000  0.473  0.890  1.0
  Ta  Ta20  1  0.000  0.808  0.703  1.0
  Ta  Ta21  1  0.500  0.308  0.797  1.0
  Ta  Ta22  1  0.000  0.918  0.243  1.0
  Ta  Ta23  1  0.500  0.027  0.390  1.0
  As  As24  1  0.000  0.423  0.704  1.0
  As  As25  1  0.000  0.248  0.919  1.0
  As  As26  1  0.000  0.311  0.151  1.0
  As  As27  1  0.500  0.748  0.581  1.0
  As  As28  1  0.500  0.252  0.419  1.0
  As  As29  1  0.000  0.577  0.296  1.0
  As  As30  1  0.500  0.189  0.651  1.0
  As  As31  1  0.000  0.752  0.081  1.0
  As  As32  1  0.500  0.811  0.349  1.0
  As  As33  1  0.000  0.689  0.849  1.0
  As  As34  1  0.500  0.077  0.204  1.0
  As  As35  1  0.500  0.923  0.796  1.0
[/CIF]
.