The material described by NaCa3 crystallizes in the tetragonal I4/mmm space group. Na(1) is bonded to four equivalent Ca(2) and eight equivalent Ca(1) atoms to form NaCa12 cuboctahedra that share corners with four equivalent Na(1)Ca12 cuboctahedra, corners with eight equivalent Ca(2)Na4Ca8 cuboctahedra, edges with eight equivalent Na(1)Ca12 cuboctahedra, edges with sixteen equivalent Ca(1)Na4Ca8 cuboctahedra, faces with four equivalent Na(1)Ca12 cuboctahedra, faces with six equivalent Ca(2)Na4Ca8 cuboctahedra, and faces with eight equivalent Ca(1)Na4Ca8 cuboctahedra. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to four equivalent Na(1), four equivalent Ca(1), and four equivalent Ca(2) atoms to form CaNa4Ca8 cuboctahedra that share corners with twelve equivalent Ca(1)Na4Ca8 cuboctahedra, edges with eight equivalent Na(1)Ca12 cuboctahedra, edges with eight equivalent Ca(1)Na4Ca8 cuboctahedra, edges with eight equivalent Ca(2)Na4Ca8 cuboctahedra, faces with four equivalent Na(1)Ca12 cuboctahedra, faces with four equivalent Ca(2)Na4Ca8 cuboctahedra, and faces with ten equivalent Ca(1)Na4Ca8 cuboctahedra. In the second Ca site, Ca(2) is bonded to four equivalent Na(1) and eight equivalent Ca(1) atoms to form CaNa4Ca8 cuboctahedra that share corners with four equivalent Ca(2)Na4Ca8 cuboctahedra, corners with eight equivalent Na(1)Ca12 cuboctahedra, edges with eight equivalent Ca(2)Na4Ca8 cuboctahedra, edges with sixteen equivalent Ca(1)Na4Ca8 cuboctahedra, faces with four equivalent Ca(2)Na4Ca8 cuboctahedra, faces with six equivalent Na(1)Ca12 cuboctahedra, and faces with eight equivalent Ca(1)Na4Ca8 cuboctahedra. is represented by the CIF card [CIF]
data_NaCa3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.901
_cell_length_b   6.901
_cell_length_c   6.901
_cell_angle_alpha   133.703
_cell_angle_beta   133.703
_cell_angle_gamma   67.552
_symmetry_Int_Tables_number   1
_cell_volume   168.903
_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
  Na  Na0  1  0.000  0.000  0.000  1.0
  Ca  Ca1  1  0.750  0.250  0.500  1.0
  Ca  Ca2  1  0.250  0.750  0.500  1.0
  Ca  Ca3  1  0.500  0.500  0.000  1.0
[/CIF]
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The material described by NaCa3 crystallizes in the tetragonal I4/mmm space group. Na(1) is bonded to four equivalent Ca(2) and eight equivalent Ca(1) atoms to form NaCa12 cuboctahedra that share corners with four equivalent Na(1)Ca12 cuboctahedra, corners with eight equivalent Ca(2)Na4Ca8 cuboctahedra, edges with eight equivalent Na(1)Ca12 cuboctahedra, edges with sixteen equivalent Ca(1)Na4Ca8 cuboctahedra, faces with four equivalent Na(1)Ca12 cuboctahedra, faces with six equivalent Ca(2)Na4Ca8 cuboctahedra, and faces with eight equivalent Ca(1)Na4Ca8 cuboctahedra. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to four equivalent Na(1), four equivalent Ca(1), and four equivalent Ca(2) atoms to form CaNa4Ca8 cuboctahedra that share corners with twelve equivalent Ca(1)Na4Ca8 cuboctahedra, edges with eight equivalent Na(1)Ca12 cuboctahedra, edges with eight equivalent Ca(1)Na4Ca8 cuboctahedra, edges with eight equivalent Ca(2)Na4Ca8 cuboctahedra, faces with four equivalent Na(1)Ca12 cuboctahedra, faces with four equivalent Ca(2)Na4Ca8 cuboctahedra, and faces with ten equivalent Ca(1)Na4Ca8 cuboctahedra. In the second Ca site, Ca(2) is bonded to four equivalent Na(1) and eight equivalent Ca(1) atoms to form CaNa4Ca8 cuboctahedra that share corners with four equivalent Ca(2)Na4Ca8 cuboctahedra, corners with eight equivalent Na(1)Ca12 cuboctahedra, edges with eight equivalent Ca(2)Na4Ca8 cuboctahedra, edges with sixteen equivalent Ca(1)Na4Ca8 cuboctahedra, faces with four equivalent Ca(2)Na4Ca8 cuboctahedra, faces with six equivalent Na(1)Ca12 cuboctahedra, and faces with eight equivalent Ca(1)Na4Ca8 cuboctahedra. is represented by the CIF card [CIF]
data_NaCa3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.901
_cell_length_b   6.901
_cell_length_c   6.901
_cell_angle_alpha   133.703
_cell_angle_beta   133.703
_cell_angle_gamma   67.552
_symmetry_Int_Tables_number   1
_cell_volume   168.903
_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
  Na  Na0  1  0.000  0.000  0.000  1.0
  Ca  Ca1  1  0.750  0.250  0.500  1.0
  Ca  Ca2  1  0.250  0.750  0.500  1.0
  Ca  Ca3  1  0.500  0.500  0.000  1.0
[/CIF]
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