The compound described by Na2Ca2(SO4)3 crystallizes in the monoclinic C2/c space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 8-coordinate geometry to two equivalent O(1), two equivalent O(3), two equivalent O(5), and two equivalent O(6) atoms. In the second Na site, Na(2) is bonded in a distorted hexagonal planar geometry to two equivalent O(4), two equivalent O(5), and two equivalent O(6) atoms. Ca(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom to form CaO6 octahedra that share corners with two equivalent S(2)O4 tetrahedra and corners with four equivalent S(1)O4 tetrahedra. There are two inequivalent S sites. In the first S site, S(1) is bonded to one O(1), one O(3), one O(4), and one O(6) atom to form SO4 tetrahedra that share corners with four equivalent Ca(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 23-38°. In the second S site, S(2) is bonded to two equivalent O(2) and two equivalent O(5) atoms to form SO4 tetrahedra that share corners with four equivalent Ca(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 25-39°. There are six inequivalent O sites. In the first O site, O(4) is bonded in a 3-coordinate geometry to one Na(2), one Ca(1), and one S(1) atom. In the second O site, O(5) is bonded in a distorted rectangular see-saw-like geometry to one Na(1), one Na(2), one Ca(1), and one S(2) atom. In the third O site, O(6) is bonded in a distorted rectangular see-saw-like geometry to one Na(1), one Na(2), one Ca(1), and one S(1) atom. In the fourth O site, O(1) is bonded in a distorted bent 150 degrees geometry to one Na(1), one Ca(1), and one S(1) atom. In the fifth O site, O(2) is bonded in a bent 150 degrees geometry to one Ca(1) and one S(2) atom. In the sixth O site, O(3) is bonded in a 3-coordinate geometry to one Na(1), one Ca(1), and one S(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na2Ca2(SO4)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.255
_cell_length_b   9.333
_cell_length_c   9.650
_cell_angle_alpha   61.414
_cell_angle_beta   61.344
_cell_angle_gamma   60.277
_symmetry_Int_Tables_number   1
_cell_volume   602.709
_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
  Ca  Ca0  1  0.363  0.340  0.953  1.0
  Ca  Ca1  1  0.845  0.840  0.453  1.0
  Ca  Ca2  1  0.637  0.660  0.047  1.0
  Ca  Ca3  1  0.155  0.160  0.547  1.0
  Na  Na4  1  0.887  0.250  0.250  1.0
  Na  Na5  1  0.113  0.750  0.750  1.0
  Na  Na6  1  0.500  0.500  0.500  1.0
  Na  Na7  1  0.000  0.000  0.000  1.0
  O  O8  1  0.275  0.105  0.111  1.0
  O  O9  1  0.525  0.284  0.099  1.0
  O  O10  1  0.100  0.524  0.088  1.0
  O  O11  1  0.592  0.784  0.599  1.0
  O  O12  1  0.009  0.605  0.611  1.0
  O  O13  1  0.789  0.024  0.588  1.0
  O  O14  1  0.725  0.895  0.889  1.0
  O  O15  1  0.475  0.716  0.901  1.0
  O  O16  1  0.900  0.476  0.912  1.0
  O  O17  1  0.408  0.216  0.401  1.0
  O  O18  1  0.991  0.395  0.389  1.0
  O  O19  1  0.211  0.976  0.412  1.0
  O  O20  1  0.604  0.210  0.759  1.0
  O  O21  1  0.417  0.599  0.760  1.0
  O  O22  1  0.210  0.441  0.765  1.0
  O  O23  1  0.724  0.099  0.260  1.0
  O  O24  1  0.927  0.710  0.259  1.0
  O  O25  1  0.084  0.941  0.265  1.0
  O  O26  1  0.396  0.790  0.241  1.0
  O  O27  1  0.583  0.401  0.240  1.0
  O  O28  1  0.790  0.559  0.235  1.0
  O  O29  1  0.276  0.901  0.740  1.0
  O  O30  1  0.073  0.290  0.741  1.0
  O  O31  1  0.916  0.059  0.735  1.0
  S  S32  1  0.245  0.952  0.257  1.0
  S  S33  1  0.556  0.250  0.250  1.0
  S  S34  1  0.953  0.548  0.243  1.0
  S  S35  1  0.444  0.750  0.750  1.0
  S  S36  1  0.047  0.452  0.757  1.0
  S  S37  1  0.755  0.048  0.743  1.0
[/CIF]
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The compound described by Na2Ca2(SO4)3 crystallizes in the monoclinic C2/c space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 8-coordinate geometry to two equivalent O(1), two equivalent O(3), two equivalent O(5), and two equivalent O(6) atoms. In the second Na site, Na(2) is bonded in a distorted hexagonal planar geometry to two equivalent O(4), two equivalent O(5), and two equivalent O(6) atoms. Ca(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom to form CaO6 octahedra that share corners with two equivalent S(2)O4 tetrahedra and corners with four equivalent S(1)O4 tetrahedra. There are two inequivalent S sites. In the first S site, S(1) is bonded to one O(1), one O(3), one O(4), and one O(6) atom to form SO4 tetrahedra that share corners with four equivalent Ca(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 23-38°. In the second S site, S(2) is bonded to two equivalent O(2) and two equivalent O(5) atoms to form SO4 tetrahedra that share corners with four equivalent Ca(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 25-39°. There are six inequivalent O sites. In the first O site, O(4) is bonded in a 3-coordinate geometry to one Na(2), one Ca(1), and one S(1) atom. In the second O site, O(5) is bonded in a distorted rectangular see-saw-like geometry to one Na(1), one Na(2), one Ca(1), and one S(2) atom. In the third O site, O(6) is bonded in a distorted rectangular see-saw-like geometry to one Na(1), one Na(2), one Ca(1), and one S(1) atom. In the fourth O site, O(1) is bonded in a distorted bent 150 degrees geometry to one Na(1), one Ca(1), and one S(1) atom. In the fifth O site, O(2) is bonded in a bent 150 degrees geometry to one Ca(1) and one S(2) atom. In the sixth O site, O(3) is bonded in a 3-coordinate geometry to one Na(1), one Ca(1), and one S(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na2Ca2(SO4)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.255
_cell_length_b   9.333
_cell_length_c   9.650
_cell_angle_alpha   61.414
_cell_angle_beta   61.344
_cell_angle_gamma   60.277
_symmetry_Int_Tables_number   1
_cell_volume   602.709
_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
  Ca  Ca0  1  0.363  0.340  0.953  1.0
  Ca  Ca1  1  0.845  0.840  0.453  1.0
  Ca  Ca2  1  0.637  0.660  0.047  1.0
  Ca  Ca3  1  0.155  0.160  0.547  1.0
  Na  Na4  1  0.887  0.250  0.250  1.0
  Na  Na5  1  0.113  0.750  0.750  1.0
  Na  Na6  1  0.500  0.500  0.500  1.0
  Na  Na7  1  0.000  0.000  0.000  1.0
  O  O8  1  0.275  0.105  0.111  1.0
  O  O9  1  0.525  0.284  0.099  1.0
  O  O10  1  0.100  0.524  0.088  1.0
  O  O11  1  0.592  0.784  0.599  1.0
  O  O12  1  0.009  0.605  0.611  1.0
  O  O13  1  0.789  0.024  0.588  1.0
  O  O14  1  0.725  0.895  0.889  1.0
  O  O15  1  0.475  0.716  0.901  1.0
  O  O16  1  0.900  0.476  0.912  1.0
  O  O17  1  0.408  0.216  0.401  1.0
  O  O18  1  0.991  0.395  0.389  1.0
  O  O19  1  0.211  0.976  0.412  1.0
  O  O20  1  0.604  0.210  0.759  1.0
  O  O21  1  0.417  0.599  0.760  1.0
  O  O22  1  0.210  0.441  0.765  1.0
  O  O23  1  0.724  0.099  0.260  1.0
  O  O24  1  0.927  0.710  0.259  1.0
  O  O25  1  0.084  0.941  0.265  1.0
  O  O26  1  0.396  0.790  0.241  1.0
  O  O27  1  0.583  0.401  0.240  1.0
  O  O28  1  0.790  0.559  0.235  1.0
  O  O29  1  0.276  0.901  0.740  1.0
  O  O30  1  0.073  0.290  0.741  1.0
  O  O31  1  0.916  0.059  0.735  1.0
  S  S32  1  0.245  0.952  0.257  1.0
  S  S33  1  0.556  0.250  0.250  1.0
  S  S34  1  0.953  0.548  0.243  1.0
  S  S35  1  0.444  0.750  0.750  1.0
  S  S36  1  0.047  0.452  0.757  1.0
  S  S37  1  0.755  0.048  0.743  1.0
[/CIF]
.