The compound described by Na3MgTaSi2SO12 crystallizes in the monoclinic Cc space group. There are three inequivalent Na sites. In the first Na site, Na(1) is bonded in a 8-coordinate geometry to one O(1), one O(10), one O(11), one O(3), one O(7), one O(9), and two equivalent O(5) atoms. In the second Na site, Na(2) is bonded in a 6-coordinate geometry to one O(10), one O(12), one O(2), one O(4), one O(7), and one O(8) atom. In the third Na site, Na(3) is bonded in a 6-coordinate geometry to one O(10), one O(11), one O(12), one O(7), one O(8), and one O(9) atom. Mg(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 distorted MgO6 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 Mg(1)O6 octahedra and corners with two equivalent Ta(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 24-37°. 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 Mg(1)O6 octahedra and corners with two equivalent Ta(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 19-37°. 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 Mg(1)O6 octahedra and corners with two equivalent Ta(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 23-39°. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Na(1), one Mg(1), and one S(1) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Na(2), one Mg(1), and one Si(1) atom. In the third O site, O(3) is bonded in a 2-coordinate geometry to one Na(1), one Mg(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(2), one Ta(1), and one Si(2) atom. In the fifth O site, O(5) is bonded in a distorted bent 150 degrees geometry to two equivalent Na(1), one Ta(1), and one Si(1) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Ta(1) and one S(1) atom. In the seventh O site, O(7) is bonded to one Na(1), one Na(2), one Na(3), one Mg(1), and one Si(2) atom to form distorted ONa3MgSi trigonal bipyramids that share  a cornercorner with one O(12)Na2TaSi trigonal pyramid,  an edgeedge with one O(12)Na2TaSi trigonal pyramid, and  a faceface with one O(8)Na2MgSi trigonal pyramid. In the eighth O site, O(8) is bonded to one Na(2), one Na(3), one Mg(1), and one Si(1) atom to form distorted ONa2MgSi trigonal pyramids that share corners with two equivalent O(12)Na2TaSi trigonal pyramids and  a faceface with one O(7)Na3MgSi trigonal bipyramid. In the ninth O site, O(9) is bonded in a 4-coordinate geometry to one Na(1), one Na(3), one Mg(1), and one S(1) atom. In the tenth O site, O(10) is bonded in a 5-coordinate geometry to one Na(1), one Na(2), one Na(3), one Ta(1), and one S(1) atom. In the eleventh O site, O(11) is bonded in a 4-coordinate geometry to one Na(1), one Na(3), one Ta(1), and one Si(1) atom. In the twelfth O site, O(12) is bonded to one Na(2), one Na(3), one Ta(1), and one Si(2) atom to form distorted ONa2TaSi trigonal pyramids that share  a cornercorner with one O(7)Na3MgSi trigonal bipyramid, corners with two equivalent O(8)Na2MgSi trigonal pyramids, and  an edgeedge with one O(7)Na3MgSi trigonal bipyramid. is represented by the CIF card [CIF]
data_Na3MgTaSi2SO12
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.018
_cell_length_b   9.018
_cell_length_c   9.081
_cell_angle_alpha   90.869
_cell_angle_beta   119.163
_cell_angle_gamma   119.605
_symmetry_Int_Tables_number   1
_cell_volume   527.826
_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
  Mg  Mg0  1  0.301  0.666  0.942  1.0
  Mg  Mg1  1  0.276  0.141  0.442  1.0
  Na  Na2  1  0.477  0.082  0.236  1.0
  Na  Na3  1  0.895  0.781  0.264  1.0
  Na  Na4  1  0.154  0.259  0.736  1.0
  Na  Na5  1  0.483  0.869  0.764  1.0
  Na  Na6  1  0.036  0.520  0.521  1.0
  Na  Na7  1  0.001  0.985  0.021  1.0
  O  O8  1  0.366  0.476  0.081  1.0
  O  O9  1  0.591  0.872  0.069  1.0
  O  O10  1  0.215  0.711  0.082  1.0
  O  O11  1  0.197  0.978  0.569  1.0
  O  O12  1  0.605  0.215  0.581  1.0
  O  O13  1  0.371  0.368  0.582  1.0
  O  O14  1  0.649  0.511  0.932  1.0
  O  O15  1  0.418  0.145  0.921  1.0
  O  O16  1  0.778  0.277  0.905  1.0
  O  O17  1  0.776  0.002  0.421  1.0
  O  O18  1  0.421  0.783  0.432  1.0
  O  O19  1  0.629  0.627  0.405  1.0
  O  O20  1  0.341  0.564  0.768  1.0
  O  O21  1  0.186  0.770  0.762  1.0
  O  O22  1  0.981  0.394  0.773  1.0
  O  O23  1  0.992  0.076  0.262  1.0
  O  O24  1  0.204  0.926  0.268  1.0
  O  O25  1  0.379  0.292  0.273  1.0
  O  O26  1  0.663  0.455  0.241  1.0
  O  O27  1  0.781  0.226  0.229  1.0
  O  O28  1  0.999  0.572  0.232  1.0
  O  O29  1  0.003  0.948  0.729  1.0
  O  O30  1  0.787  0.078  0.741  1.0
  O  O31  1  0.660  0.733  0.732  1.0
  S  S32  1  0.496  0.458  0.245  1.0
  S  S33  1  0.787  0.249  0.745  1.0
  Si  Si34  1  0.791  0.045  0.241  1.0
  Si  Si35  1  0.205  0.748  0.245  1.0
  Si  Si36  1  0.196  0.950  0.741  1.0
  Si  Si37  1  0.497  0.541  0.745  1.0
  Ta  Ta38  1  0.708  0.359  0.061  1.0
  Ta  Ta39  1  0.702  0.852  0.561  1.0
[/CIF]
.
The compound described by Na3MgTaSi2SO12 crystallizes in the monoclinic Cc space group. There are three inequivalent Na sites. In the first Na site, Na(1) is bonded in a 8-coordinate geometry to one O(1), one O(10), one O(11), one O(3), one O(7), one O(9), and two equivalent O(5) atoms. In the second Na site, Na(2) is bonded in a 6-coordinate geometry to one O(10), one O(12), one O(2), one O(4), one O(7), and one O(8) atom. In the third Na site, Na(3) is bonded in a 6-coordinate geometry to one O(10), one O(11), one O(12), one O(7), one O(8), and one O(9) atom. Mg(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 distorted MgO6 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 Mg(1)O6 octahedra and corners with two equivalent Ta(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 24-37°. 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 Mg(1)O6 octahedra and corners with two equivalent Ta(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 19-37°. 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 Mg(1)O6 octahedra and corners with two equivalent Ta(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 23-39°. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Na(1), one Mg(1), and one S(1) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Na(2), one Mg(1), and one Si(1) atom. In the third O site, O(3) is bonded in a 2-coordinate geometry to one Na(1), one Mg(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(2), one Ta(1), and one Si(2) atom. In the fifth O site, O(5) is bonded in a distorted bent 150 degrees geometry to two equivalent Na(1), one Ta(1), and one Si(1) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Ta(1) and one S(1) atom. In the seventh O site, O(7) is bonded to one Na(1), one Na(2), one Na(3), one Mg(1), and one Si(2) atom to form distorted ONa3MgSi trigonal bipyramids that share  a cornercorner with one O(12)Na2TaSi trigonal pyramid,  an edgeedge with one O(12)Na2TaSi trigonal pyramid, and  a faceface with one O(8)Na2MgSi trigonal pyramid. In the eighth O site, O(8) is bonded to one Na(2), one Na(3), one Mg(1), and one Si(1) atom to form distorted ONa2MgSi trigonal pyramids that share corners with two equivalent O(12)Na2TaSi trigonal pyramids and  a faceface with one O(7)Na3MgSi trigonal bipyramid. In the ninth O site, O(9) is bonded in a 4-coordinate geometry to one Na(1), one Na(3), one Mg(1), and one S(1) atom. In the tenth O site, O(10) is bonded in a 5-coordinate geometry to one Na(1), one Na(2), one Na(3), one Ta(1), and one S(1) atom. In the eleventh O site, O(11) is bonded in a 4-coordinate geometry to one Na(1), one Na(3), one Ta(1), and one Si(1) atom. In the twelfth O site, O(12) is bonded to one Na(2), one Na(3), one Ta(1), and one Si(2) atom to form distorted ONa2TaSi trigonal pyramids that share  a cornercorner with one O(7)Na3MgSi trigonal bipyramid, corners with two equivalent O(8)Na2MgSi trigonal pyramids, and  an edgeedge with one O(7)Na3MgSi trigonal bipyramid. is represented by the CIF card [CIF]
data_Na3MgTaSi2SO12
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.018
_cell_length_b   9.018
_cell_length_c   9.081
_cell_angle_alpha   90.869
_cell_angle_beta   119.163
_cell_angle_gamma   119.605
_symmetry_Int_Tables_number   1
_cell_volume   527.826
_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
  Mg  Mg0  1  0.301  0.666  0.942  1.0
  Mg  Mg1  1  0.276  0.141  0.442  1.0
  Na  Na2  1  0.477  0.082  0.236  1.0
  Na  Na3  1  0.895  0.781  0.264  1.0
  Na  Na4  1  0.154  0.259  0.736  1.0
  Na  Na5  1  0.483  0.869  0.764  1.0
  Na  Na6  1  0.036  0.520  0.521  1.0
  Na  Na7  1  0.001  0.985  0.021  1.0
  O  O8  1  0.366  0.476  0.081  1.0
  O  O9  1  0.591  0.872  0.069  1.0
  O  O10  1  0.215  0.711  0.082  1.0
  O  O11  1  0.197  0.978  0.569  1.0
  O  O12  1  0.605  0.215  0.581  1.0
  O  O13  1  0.371  0.368  0.582  1.0
  O  O14  1  0.649  0.511  0.932  1.0
  O  O15  1  0.418  0.145  0.921  1.0
  O  O16  1  0.778  0.277  0.905  1.0
  O  O17  1  0.776  0.002  0.421  1.0
  O  O18  1  0.421  0.783  0.432  1.0
  O  O19  1  0.629  0.627  0.405  1.0
  O  O20  1  0.341  0.564  0.768  1.0
  O  O21  1  0.186  0.770  0.762  1.0
  O  O22  1  0.981  0.394  0.773  1.0
  O  O23  1  0.992  0.076  0.262  1.0
  O  O24  1  0.204  0.926  0.268  1.0
  O  O25  1  0.379  0.292  0.273  1.0
  O  O26  1  0.663  0.455  0.241  1.0
  O  O27  1  0.781  0.226  0.229  1.0
  O  O28  1  0.999  0.572  0.232  1.0
  O  O29  1  0.003  0.948  0.729  1.0
  O  O30  1  0.787  0.078  0.741  1.0
  O  O31  1  0.660  0.733  0.732  1.0
  S  S32  1  0.496  0.458  0.245  1.0
  S  S33  1  0.787  0.249  0.745  1.0
  Si  Si34  1  0.791  0.045  0.241  1.0
  Si  Si35  1  0.205  0.748  0.245  1.0
  Si  Si36  1  0.196  0.950  0.741  1.0
  Si  Si37  1  0.497  0.541  0.745  1.0
  Ta  Ta38  1  0.708  0.359  0.061  1.0
  Ta  Ta39  1  0.702  0.852  0.561  1.0
[/CIF]
.