data_La2TaOs
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.29
_cell_length_b   3.29
_cell_length_c   9.29
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   La2TaOs
_chemical_formula_sum   'La2 Ta1 Os1'
_cell_volume   100.29
_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
  La  La0  1  0.64  0.64  0.78  1.0
  La  La1  1  0.0  0.0  0.95  1.0
  Ta  Ta3  1  0.0  0.0  0.42  1.0
  Os  Os2  1  0.64  0.64  0.08  1.0

data_La2TaOs
_symmetry_space_group_name_H-M   Cm
_cell_length_a   4.65
_cell_length_b   4.65
_cell_length_c   9.29
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   La2TaOs
_chemical_formula_sum   'La4 Ta2 Os2'
_cell_volume   200.58
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  'x, -y, z'
  3  'x+1/2, y+1/2, z'
  4  'x+1/2, -y+1/2, 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
  La  La0  2  0.0  0.0  0.95  1.0
  La  La1  2  0.14  0.5  0.78  1.0
  Ta  Ta2  2  0.0  0.0  0.42  1.0
  Os  Os3  2  0.14  0.5  0.08  1.0

La La Ta Os
La La Ta Os 0 1 o + o 0 1 + o o 0 1 + + o 0 3 o o + 0 2 + + o 1 3 - - + 2 3 - - o 2 3 - o o 2 3 o - o 2 2 + o o 2 2 o + o 
La2TaOs crystallizes in the monoclinic Cm space group. There are two inequivalent La sites. In the first La site, La(1) is bonded in a 2-coordinate geometry to one La(2), three equivalent Ta(1), and one Os(1) atom. The La(1)-La(2) bond length is 2.24 Å. There is one shorter (3.77 Å) and two longer (4.16 Å) La(1)-Ta(1) bond lengths. The La(1)-Os(1) bond length is 2.70 Å. In the second La site, La(2) is bonded in a 1-coordinate geometry to one La(1) and one Os(1) atom. The La(2)-Os(1) bond length is 2.05 Å. Ta(1) is bonded in a 8-coordinate geometry to three equivalent La(1), four equivalent Ta(1), and one Os(1) atom. All Ta(1)-Ta(1) bond lengths are 3.29 Å. The Ta(1)-Os(1) bond length is 3.60 Å. Os(1) is bonded in a 1-coordinate geometry to one La(1), one La(2), and one Ta(1) atom.