The material described by Na4CaSn6 crystallizes in the hexagonal P6_3/mmc space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 4-coordinate geometry to eight equivalent Sn(1) atoms. In the second Na site, Na(2) is bonded in a 6-coordinate geometry to six equivalent Sn(1) atoms. Ca(1) is bonded in a 12-coordinate geometry to twelve equivalent Sn(1) atoms. Sn(1) is bonded in a 10-coordinate geometry to one Na(2), four equivalent Na(1), two equivalent Ca(1), and three equivalent Sn(1) atoms. is represented by the CIF card [CIF]
data_Na4CaSn6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.145
_cell_length_b   10.145
_cell_length_c   7.232
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   644.608
_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
  Na  Na0  1  0.541  0.459  0.750  1.0
  Na  Na1  1  0.541  0.081  0.750  1.0
  Na  Na2  1  0.459  0.541  0.250  1.0
  Na  Na3  1  0.081  0.541  0.250  1.0
  Na  Na4  1  0.667  0.333  0.250  1.0
  Na  Na5  1  0.919  0.459  0.750  1.0
  Na  Na6  1  0.333  0.667  0.750  1.0
  Na  Na7  1  0.459  0.919  0.250  1.0
  Ca  Ca8  1  0.000  0.000  0.750  1.0
  Ca  Ca9  1  0.000  0.000  0.250  1.0
  Sn  Sn10  1  0.831  0.169  0.461  1.0
  Sn  Sn11  1  0.831  0.169  0.039  1.0
  Sn  Sn12  1  0.831  0.662  0.461  1.0
  Sn  Sn13  1  0.662  0.831  0.961  1.0
  Sn  Sn14  1  0.169  0.831  0.539  1.0
  Sn  Sn15  1  0.169  0.338  0.539  1.0
  Sn  Sn16  1  0.169  0.338  0.961  1.0
  Sn  Sn17  1  0.831  0.662  0.039  1.0
  Sn  Sn18  1  0.169  0.831  0.961  1.0
  Sn  Sn19  1  0.338  0.169  0.039  1.0
  Sn  Sn20  1  0.662  0.831  0.539  1.0
  Sn  Sn21  1  0.338  0.169  0.461  1.0
[/CIF]
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The material described by Na4CaSn6 crystallizes in the hexagonal P6_3/mmc space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 4-coordinate geometry to eight equivalent Sn(1) atoms. In the second Na site, Na(2) is bonded in a 6-coordinate geometry to six equivalent Sn(1) atoms. Ca(1) is bonded in a 12-coordinate geometry to twelve equivalent Sn(1) atoms. Sn(1) is bonded in a 10-coordinate geometry to one Na(2), four equivalent Na(1), two equivalent Ca(1), and three equivalent Sn(1) atoms. is represented by the CIF card [CIF]
data_Na4CaSn6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.145
_cell_length_b   10.145
_cell_length_c   7.232
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   644.608
_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
  Na  Na0  1  0.541  0.459  0.750  1.0
  Na  Na1  1  0.541  0.081  0.750  1.0
  Na  Na2  1  0.459  0.541  0.250  1.0
  Na  Na3  1  0.081  0.541  0.250  1.0
  Na  Na4  1  0.667  0.333  0.250  1.0
  Na  Na5  1  0.919  0.459  0.750  1.0
  Na  Na6  1  0.333  0.667  0.750  1.0
  Na  Na7  1  0.459  0.919  0.250  1.0
  Ca  Ca8  1  0.000  0.000  0.750  1.0
  Ca  Ca9  1  0.000  0.000  0.250  1.0
  Sn  Sn10  1  0.831  0.169  0.461  1.0
  Sn  Sn11  1  0.831  0.169  0.039  1.0
  Sn  Sn12  1  0.831  0.662  0.461  1.0
  Sn  Sn13  1  0.662  0.831  0.961  1.0
  Sn  Sn14  1  0.169  0.831  0.539  1.0
  Sn  Sn15  1  0.169  0.338  0.539  1.0
  Sn  Sn16  1  0.169  0.338  0.961  1.0
  Sn  Sn17  1  0.831  0.662  0.039  1.0
  Sn  Sn18  1  0.169  0.831  0.961  1.0
  Sn  Sn19  1  0.338  0.169  0.039  1.0
  Sn  Sn20  1  0.662  0.831  0.539  1.0
  Sn  Sn21  1  0.338  0.169  0.461  1.0
[/CIF]
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