The structure described by Na2LaTaSi2SO12 crystallizes in the monoclinic Cc space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 8-coordinate geometry to one O(10), one O(12), one O(4), one O(6), one O(7), one O(8), and two equivalent O(2) atoms. In the second Na site, Na(2) is bonded in a 5-coordinate geometry to one O(10), one O(11), one O(12), one O(7), and one O(8) atom. La(1) is bonded to one O(1), one O(2), one O(3), one O(7), one O(8), and one O(9) atom to form LaO6 octahedra that share corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra, and corners with two equivalent S(1)O4 tetrahedra. Ta(1) is bonded to one O(10), one O(11), one O(12), one O(4), one O(5), and one O(6) atom to form TaO6 octahedra that share corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra, and corners with two equivalent S(1)O4 tetrahedra. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(11), one O(2), one O(5), and one O(8) atom to form SiO4 tetrahedra that share corners with two equivalent La(1)O6 octahedra and corners with two equivalent Ta(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 15-38°. In the second Si site, Si(2) is bonded to one O(12), one O(3), one O(4), and one O(7) atom to form SiO4 tetrahedra that share corners with two equivalent La(1)O6 octahedra and corners with two equivalent Ta(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 23-36°. S(1) is bonded to one O(1), one O(10), one O(6), and one O(9) atom to form SO4 tetrahedra that share corners with two equivalent La(1)O6 octahedra and corners with two equivalent Ta(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 21-44°. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one La(1) and one S(1) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to two equivalent Na(1), one La(1), and one Si(1) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one La(1) and one Si(2) atom. In the fourth O site, O(4) is bonded in a distorted bent 150 degrees geometry to one Na(1), one Ta(1), and one Si(2) atom. In the fifth O site, O(5) is bonded in a linear geometry to one Ta(1) and one Si(1) atom. In the sixth O site, O(6) is bonded in a distorted bent 150 degrees geometry to one Na(1), one Ta(1), and one S(1) atom. In the seventh O site, O(7) is bonded in a rectangular see-saw-like geometry to one Na(1), one Na(2), one La(1), and one Si(2) atom. In the eighth O site, O(8) is bonded in a 4-coordinate geometry to one Na(1), one Na(2), one La(1), and one Si(1) atom. In the ninth O site, O(9) is bonded in a distorted bent 150 degrees geometry to one La(1) and one S(1) atom. In the tenth O site, O(10) is bonded in a 4-coordinate geometry to one Na(1), one Na(2), one Ta(1), and one S(1) atom. In the eleventh O site, O(11) is bonded in a 3-coordinate geometry to one Na(2), one Ta(1), and one Si(1) atom. In the twelfth O site, O(12) is bonded in a 3-coordinate geometry to one Na(1), one Na(2), one Ta(1), and one Si(2) atom. is represented by the CIF file [CIF]
data_Na2LaTaSi2SO12
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.267
_cell_length_b   9.342
_cell_length_c   9.342
_cell_angle_alpha   61.410
_cell_angle_beta   61.197
_cell_angle_gamma   61.197
_symmetry_Int_Tables_number   1
_cell_volume   588.235
_cell_formula_units_Z   2
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  0.058  0.659  0.651  1.0
  La  La1  1  0.558  0.151  0.159  1.0
  Na  Na2  1  0.745  0.383  0.776  1.0
  Na  Na3  1  0.245  0.276  0.883  1.0
  Na  Na4  1  0.497  0.474  0.493  1.0
  Na  Na5  1  0.997  0.993  0.974  1.0
  O  O6  1  0.908  0.698  0.476  1.0
  O  O7  1  0.933  0.475  0.888  1.0
  O  O8  1  0.919  0.910  0.687  1.0
  O  O9  1  0.433  0.388  0.975  1.0
  O  O10  1  0.408  0.976  0.198  1.0
  O  O11  1  0.419  0.187  0.410  1.0
  O  O12  1  0.071  0.279  0.510  1.0
  O  O13  1  0.093  0.487  0.154  1.0
  O  O14  1  0.094  0.128  0.261  1.0
  O  O15  1  0.593  0.654  0.987  1.0
  O  O16  1  0.571  0.010  0.779  1.0
  O  O17  1  0.594  0.761  0.628  1.0
  O  O18  1  0.238  0.382  0.608  1.0
  O  O19  1  0.236  0.584  0.793  1.0
  O  O20  1  0.219  0.808  0.355  1.0
  O  O21  1  0.736  0.293  0.084  1.0
  O  O22  1  0.738  0.108  0.882  1.0
  O  O23  1  0.719  0.855  0.308  1.0
  O  O24  1  0.750  0.555  0.474  1.0
  O  O25  1  0.779  0.455  0.224  1.0
  O  O26  1  0.770  0.239  0.547  1.0
  O  O27  1  0.279  0.724  0.955  1.0
  O  O28  1  0.250  0.974  0.055  1.0
  O  O29  1  0.270  0.047  0.739  1.0
  S  S30  1  0.743  0.726  0.469  1.0
  S  S31  1  0.243  0.969  0.226  1.0
  Si  Si32  1  0.758  0.469  0.049  1.0
  Si  Si33  1  0.748  0.065  0.729  1.0
  Si  Si34  1  0.258  0.549  0.969  1.0
  Si  Si35  1  0.248  0.229  0.565  1.0
  Ta  Ta36  1  0.941  0.358  0.355  1.0
  Ta  Ta37  1  0.441  0.855  0.858  1.0
[/CIF]
.
The structure described by Na2LaTaSi2SO12 crystallizes in the monoclinic Cc space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 8-coordinate geometry to one O(10), one O(12), one O(4), one O(6), one O(7), one O(8), and two equivalent O(2) atoms. In the second Na site, Na(2) is bonded in a 5-coordinate geometry to one O(10), one O(11), one O(12), one O(7), and one O(8) atom. La(1) is bonded to one O(1), one O(2), one O(3), one O(7), one O(8), and one O(9) atom to form LaO6 octahedra that share corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra, and corners with two equivalent S(1)O4 tetrahedra. Ta(1) is bonded to one O(10), one O(11), one O(12), one O(4), one O(5), and one O(6) atom to form TaO6 octahedra that share corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra, and corners with two equivalent S(1)O4 tetrahedra. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(11), one O(2), one O(5), and one O(8) atom to form SiO4 tetrahedra that share corners with two equivalent La(1)O6 octahedra and corners with two equivalent Ta(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 15-38°. In the second Si site, Si(2) is bonded to one O(12), one O(3), one O(4), and one O(7) atom to form SiO4 tetrahedra that share corners with two equivalent La(1)O6 octahedra and corners with two equivalent Ta(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 23-36°. S(1) is bonded to one O(1), one O(10), one O(6), and one O(9) atom to form SO4 tetrahedra that share corners with two equivalent La(1)O6 octahedra and corners with two equivalent Ta(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 21-44°. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one La(1) and one S(1) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to two equivalent Na(1), one La(1), and one Si(1) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one La(1) and one Si(2) atom. In the fourth O site, O(4) is bonded in a distorted bent 150 degrees geometry to one Na(1), one Ta(1), and one Si(2) atom. In the fifth O site, O(5) is bonded in a linear geometry to one Ta(1) and one Si(1) atom. In the sixth O site, O(6) is bonded in a distorted bent 150 degrees geometry to one Na(1), one Ta(1), and one S(1) atom. In the seventh O site, O(7) is bonded in a rectangular see-saw-like geometry to one Na(1), one Na(2), one La(1), and one Si(2) atom. In the eighth O site, O(8) is bonded in a 4-coordinate geometry to one Na(1), one Na(2), one La(1), and one Si(1) atom. In the ninth O site, O(9) is bonded in a distorted bent 150 degrees geometry to one La(1) and one S(1) atom. In the tenth O site, O(10) is bonded in a 4-coordinate geometry to one Na(1), one Na(2), one Ta(1), and one S(1) atom. In the eleventh O site, O(11) is bonded in a 3-coordinate geometry to one Na(2), one Ta(1), and one Si(1) atom. In the twelfth O site, O(12) is bonded in a 3-coordinate geometry to one Na(1), one Na(2), one Ta(1), and one Si(2) atom. is represented by the CIF file [CIF]
data_Na2LaTaSi2SO12
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.267
_cell_length_b   9.342
_cell_length_c   9.342
_cell_angle_alpha   61.410
_cell_angle_beta   61.197
_cell_angle_gamma   61.197
_symmetry_Int_Tables_number   1
_cell_volume   588.235
_cell_formula_units_Z   2
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  0.058  0.659  0.651  1.0
  La  La1  1  0.558  0.151  0.159  1.0
  Na  Na2  1  0.745  0.383  0.776  1.0
  Na  Na3  1  0.245  0.276  0.883  1.0
  Na  Na4  1  0.497  0.474  0.493  1.0
  Na  Na5  1  0.997  0.993  0.974  1.0
  O  O6  1  0.908  0.698  0.476  1.0
  O  O7  1  0.933  0.475  0.888  1.0
  O  O8  1  0.919  0.910  0.687  1.0
  O  O9  1  0.433  0.388  0.975  1.0
  O  O10  1  0.408  0.976  0.198  1.0
  O  O11  1  0.419  0.187  0.410  1.0
  O  O12  1  0.071  0.279  0.510  1.0
  O  O13  1  0.093  0.487  0.154  1.0
  O  O14  1  0.094  0.128  0.261  1.0
  O  O15  1  0.593  0.654  0.987  1.0
  O  O16  1  0.571  0.010  0.779  1.0
  O  O17  1  0.594  0.761  0.628  1.0
  O  O18  1  0.238  0.382  0.608  1.0
  O  O19  1  0.236  0.584  0.793  1.0
  O  O20  1  0.219  0.808  0.355  1.0
  O  O21  1  0.736  0.293  0.084  1.0
  O  O22  1  0.738  0.108  0.882  1.0
  O  O23  1  0.719  0.855  0.308  1.0
  O  O24  1  0.750  0.555  0.474  1.0
  O  O25  1  0.779  0.455  0.224  1.0
  O  O26  1  0.770  0.239  0.547  1.0
  O  O27  1  0.279  0.724  0.955  1.0
  O  O28  1  0.250  0.974  0.055  1.0
  O  O29  1  0.270  0.047  0.739  1.0
  S  S30  1  0.743  0.726  0.469  1.0
  S  S31  1  0.243  0.969  0.226  1.0
  Si  Si32  1  0.758  0.469  0.049  1.0
  Si  Si33  1  0.748  0.065  0.729  1.0
  Si  Si34  1  0.258  0.549  0.969  1.0
  Si  Si35  1  0.248  0.229  0.565  1.0
  Ta  Ta36  1  0.941  0.358  0.355  1.0
  Ta  Ta37  1  0.441  0.855  0.858  1.0
[/CIF]
.