The material structure described by Na4Ca2SiP4 crystallizes in the monoclinic Cc space group. There are four inequivalent Na sites. In the first Na site, Na(1) is bonded in a 6-coordinate geometry to one Si(1), one P(1), one P(2), one P(3), and two equivalent P(4) atoms. In the second Na site, Na(2) is bonded in a 4-coordinate geometry to one P(1), one P(4), and two equivalent P(3) atoms. In the third Na site, Na(3) is bonded in a 4-coordinate geometry to one P(1), one P(4), and two equivalent P(2) atoms. In the fourth Na site, Na(4) is bonded in a 4-coordinate geometry to one P(1), one P(2), one P(3), and one P(4) atom. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 5-coordinate geometry to one P(1), one P(2), one P(3), and two equivalent P(4) atoms. In the second Ca site, Ca(2) is bonded in a 7-coordinate geometry to one Si(1), two equivalent P(1), two equivalent P(2), and two equivalent P(3) atoms. Si(1) is bonded in a distorted tetrahedral geometry to one Na(1), one Ca(2), one P(1), one P(2), one P(3), and one P(4) atom. There are four inequivalent P sites. In the first P site, P(4) is bonded in a 8-coordinate geometry to one Na(2), one Na(3), one Na(4), two equivalent Na(1), two equivalent Ca(1), and one Si(1) atom. In the second P site, P(1) is bonded in a 7-coordinate geometry to one Na(1), one Na(2), one Na(3), one Na(4), one Ca(1), two equivalent Ca(2), and one Si(1) atom. In the third P site, P(2) is bonded in a 8-coordinate geometry to one Na(1), one Na(4), two equivalent Na(3), one Ca(1), two equivalent Ca(2), and one Si(1) atom. In the fourth P site, P(3) is bonded in a 8-coordinate geometry to one Na(1), one Na(4), two equivalent Na(2), one Ca(1), two equivalent Ca(2), and one Si(1) atom. is represented by the CIF card [CIF]
data_Na4Ca2SiP4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.153
_cell_length_b   9.153
_cell_length_c   6.986
_cell_angle_alpha   88.969
_cell_angle_beta   88.969
_cell_angle_gamma   119.593
_symmetry_Int_Tables_number   1
_cell_volume   508.602
_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  0.473  0.944  0.389  1.0
  Na  Na1  1  0.944  0.473  0.889  1.0
  Na  Na2  1  0.862  0.719  0.188  1.0
  Na  Na3  1  0.287  0.136  0.218  1.0
  Na  Na4  1  0.850  0.139  0.205  1.0
  Na  Na5  1  0.136  0.287  0.718  1.0
  Na  Na6  1  0.719  0.862  0.688  1.0
  Na  Na7  1  0.139  0.850  0.705  1.0
  Ca  Ca8  1  0.053  0.528  0.388  1.0
  Ca  Ca9  1  0.479  0.530  0.386  1.0
  Ca  Ca10  1  0.528  0.053  0.888  1.0
  Ca  Ca11  1  0.530  0.479  0.886  1.0
  Si  Si12  1  0.663  0.329  0.500  1.0
  Si  Si13  1  0.329  0.663  0.000  1.0
  P  P14  1  0.660  0.336  0.172  1.0
  P  P15  1  0.336  0.660  0.672  1.0
  P  P16  1  0.203  0.393  0.124  1.0
  P  P17  1  0.606  0.801  0.090  1.0
  P  P18  1  0.202  0.806  0.104  1.0
  P  P19  1  0.801  0.606  0.590  1.0
  P  P20  1  0.393  0.203  0.624  1.0
  P  P21  1  0.806  0.202  0.604  1.0
[/CIF]
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The material structure described by Na4Ca2SiP4 crystallizes in the monoclinic Cc space group. There are four inequivalent Na sites. In the first Na site, Na(1) is bonded in a 6-coordinate geometry to one Si(1), one P(1), one P(2), one P(3), and two equivalent P(4) atoms. In the second Na site, Na(2) is bonded in a 4-coordinate geometry to one P(1), one P(4), and two equivalent P(3) atoms. In the third Na site, Na(3) is bonded in a 4-coordinate geometry to one P(1), one P(4), and two equivalent P(2) atoms. In the fourth Na site, Na(4) is bonded in a 4-coordinate geometry to one P(1), one P(2), one P(3), and one P(4) atom. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 5-coordinate geometry to one P(1), one P(2), one P(3), and two equivalent P(4) atoms. In the second Ca site, Ca(2) is bonded in a 7-coordinate geometry to one Si(1), two equivalent P(1), two equivalent P(2), and two equivalent P(3) atoms. Si(1) is bonded in a distorted tetrahedral geometry to one Na(1), one Ca(2), one P(1), one P(2), one P(3), and one P(4) atom. There are four inequivalent P sites. In the first P site, P(4) is bonded in a 8-coordinate geometry to one Na(2), one Na(3), one Na(4), two equivalent Na(1), two equivalent Ca(1), and one Si(1) atom. In the second P site, P(1) is bonded in a 7-coordinate geometry to one Na(1), one Na(2), one Na(3), one Na(4), one Ca(1), two equivalent Ca(2), and one Si(1) atom. In the third P site, P(2) is bonded in a 8-coordinate geometry to one Na(1), one Na(4), two equivalent Na(3), one Ca(1), two equivalent Ca(2), and one Si(1) atom. In the fourth P site, P(3) is bonded in a 8-coordinate geometry to one Na(1), one Na(4), two equivalent Na(2), one Ca(1), two equivalent Ca(2), and one Si(1) atom. is represented by the CIF card [CIF]
data_Na4Ca2SiP4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.153
_cell_length_b   9.153
_cell_length_c   6.986
_cell_angle_alpha   88.969
_cell_angle_beta   88.969
_cell_angle_gamma   119.593
_symmetry_Int_Tables_number   1
_cell_volume   508.602
_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  0.473  0.944  0.389  1.0
  Na  Na1  1  0.944  0.473  0.889  1.0
  Na  Na2  1  0.862  0.719  0.188  1.0
  Na  Na3  1  0.287  0.136  0.218  1.0
  Na  Na4  1  0.850  0.139  0.205  1.0
  Na  Na5  1  0.136  0.287  0.718  1.0
  Na  Na6  1  0.719  0.862  0.688  1.0
  Na  Na7  1  0.139  0.850  0.705  1.0
  Ca  Ca8  1  0.053  0.528  0.388  1.0
  Ca  Ca9  1  0.479  0.530  0.386  1.0
  Ca  Ca10  1  0.528  0.053  0.888  1.0
  Ca  Ca11  1  0.530  0.479  0.886  1.0
  Si  Si12  1  0.663  0.329  0.500  1.0
  Si  Si13  1  0.329  0.663  0.000  1.0
  P  P14  1  0.660  0.336  0.172  1.0
  P  P15  1  0.336  0.660  0.672  1.0
  P  P16  1  0.203  0.393  0.124  1.0
  P  P17  1  0.606  0.801  0.090  1.0
  P  P18  1  0.202  0.806  0.104  1.0
  P  P19  1  0.801  0.606  0.590  1.0
  P  P20  1  0.393  0.203  0.624  1.0
  P  P21  1  0.806  0.202  0.604  1.0
[/CIF]
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