The crystal structure described by Ti3Ta crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to four equivalent Ti(1), four equivalent Ti(2), and four equivalent Ta(1) atoms to form TiTa4Ti8 cuboctahedra that share corners with twelve equivalent Ti(1)Ta4Ti8 cuboctahedra, edges with eight equivalent Ti(1)Ta4Ti8 cuboctahedra, edges with eight equivalent Ti(2)Ta4Ti8 cuboctahedra, edges with eight equivalent Ta(1)Ti12 cuboctahedra, faces with four equivalent Ti(2)Ta4Ti8 cuboctahedra, faces with four equivalent Ta(1)Ti12 cuboctahedra, and faces with ten equivalent Ti(1)Ta4Ti8 cuboctahedra. In the second Ti site, Ti(2) is bonded to eight equivalent Ti(1) and four equivalent Ta(1) atoms to form TiTa4Ti8 cuboctahedra that share corners with four equivalent Ti(2)Ta4Ti8 cuboctahedra, corners with eight equivalent Ta(1)Ti12 cuboctahedra, edges with eight equivalent Ti(2)Ta4Ti8 cuboctahedra, edges with sixteen equivalent Ti(1)Ta4Ti8 cuboctahedra, faces with four equivalent Ti(2)Ta4Ti8 cuboctahedra, faces with six equivalent Ta(1)Ti12 cuboctahedra, and faces with eight equivalent Ti(1)Ta4Ti8 cuboctahedra. Ta(1) is bonded to four equivalent Ti(2) and eight equivalent Ti(1) atoms to form TaTi12 cuboctahedra that share corners with four equivalent Ta(1)Ti12 cuboctahedra, corners with eight equivalent Ti(2)Ta4Ti8 cuboctahedra, edges with eight equivalent Ta(1)Ti12 cuboctahedra, edges with sixteen equivalent Ti(1)Ta4Ti8 cuboctahedra, faces with four equivalent Ta(1)Ti12 cuboctahedra, faces with six equivalent Ti(2)Ta4Ti8 cuboctahedra, and faces with eight equivalent Ti(1)Ta4Ti8 cuboctahedra. is represented by the CIF file [CIF]
data_TaTi3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.227
_cell_length_b   5.227
_cell_length_c   5.227
_cell_angle_alpha   135.060
_cell_angle_beta   135.060
_cell_angle_gamma   65.436
_symmetry_Int_Tables_number   1
_cell_volume   70.217
_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
  Ta  Ta0  1  0.000  0.000  0.000  1.0
  Ti  Ti1  1  0.750  0.250  0.500  1.0
  Ti  Ti2  1  0.250  0.750  0.500  1.0
  Ti  Ti3  1  0.500  0.500  0.000  1.0
[/CIF]
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The crystal structure described by Ti3Ta crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to four equivalent Ti(1), four equivalent Ti(2), and four equivalent Ta(1) atoms to form TiTa4Ti8 cuboctahedra that share corners with twelve equivalent Ti(1)Ta4Ti8 cuboctahedra, edges with eight equivalent Ti(1)Ta4Ti8 cuboctahedra, edges with eight equivalent Ti(2)Ta4Ti8 cuboctahedra, edges with eight equivalent Ta(1)Ti12 cuboctahedra, faces with four equivalent Ti(2)Ta4Ti8 cuboctahedra, faces with four equivalent Ta(1)Ti12 cuboctahedra, and faces with ten equivalent Ti(1)Ta4Ti8 cuboctahedra. In the second Ti site, Ti(2) is bonded to eight equivalent Ti(1) and four equivalent Ta(1) atoms to form TiTa4Ti8 cuboctahedra that share corners with four equivalent Ti(2)Ta4Ti8 cuboctahedra, corners with eight equivalent Ta(1)Ti12 cuboctahedra, edges with eight equivalent Ti(2)Ta4Ti8 cuboctahedra, edges with sixteen equivalent Ti(1)Ta4Ti8 cuboctahedra, faces with four equivalent Ti(2)Ta4Ti8 cuboctahedra, faces with six equivalent Ta(1)Ti12 cuboctahedra, and faces with eight equivalent Ti(1)Ta4Ti8 cuboctahedra. Ta(1) is bonded to four equivalent Ti(2) and eight equivalent Ti(1) atoms to form TaTi12 cuboctahedra that share corners with four equivalent Ta(1)Ti12 cuboctahedra, corners with eight equivalent Ti(2)Ta4Ti8 cuboctahedra, edges with eight equivalent Ta(1)Ti12 cuboctahedra, edges with sixteen equivalent Ti(1)Ta4Ti8 cuboctahedra, faces with four equivalent Ta(1)Ti12 cuboctahedra, faces with six equivalent Ti(2)Ta4Ti8 cuboctahedra, and faces with eight equivalent Ti(1)Ta4Ti8 cuboctahedra. is represented by the CIF file [CIF]
data_TaTi3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.227
_cell_length_b   5.227
_cell_length_c   5.227
_cell_angle_alpha   135.060
_cell_angle_beta   135.060
_cell_angle_gamma   65.436
_symmetry_Int_Tables_number   1
_cell_volume   70.217
_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
  Ta  Ta0  1  0.000  0.000  0.000  1.0
  Ti  Ti1  1  0.750  0.250  0.500  1.0
  Ti  Ti2  1  0.250  0.750  0.500  1.0
  Ti  Ti3  1  0.500  0.500  0.000  1.0
[/CIF]
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