The material structure described by Na4Sr2SiP4 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 Sr sites. In the first Sr site, Sr(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 Sr site, Sr(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 Sr(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 Sr(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 Sr(1), two equivalent Sr(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 Sr(1), two equivalent Sr(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 Sr(1), two equivalent Sr(2), and one Si(1) atom. is represented by the CIF card [CIF]
data_Na4Sr2SiP4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.253
_cell_length_b   9.253
_cell_length_c   7.286
_cell_angle_alpha   89.730
_cell_angle_beta   89.730
_cell_angle_gamma   119.978
_symmetry_Int_Tables_number   1
_cell_volume   540.360
_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  0.055  0.527  0.611  1.0
  Na  Na1  1  0.527  0.055  0.111  1.0
  Na  Na2  1  0.277  0.135  0.808  1.0
  Na  Na3  1  0.867  0.714  0.778  1.0
  Na  Na4  1  0.862  0.151  0.788  1.0
  Na  Na5  1  0.714  0.867  0.278  1.0
  Na  Na6  1  0.135  0.277  0.308  1.0
  Na  Na7  1  0.151  0.862  0.288  1.0
  Sr  Sr8  1  0.471  0.949  0.614  1.0
  Sr  Sr9  1  0.468  0.521  0.615  1.0
  Sr  Sr10  1  0.949  0.471  0.114  1.0
  Sr  Sr11  1  0.521  0.468  0.115  1.0
  Si  Si12  1  0.672  0.337  0.499  1.0
  Si  Si13  1  0.337  0.672  0.999  1.0
  P  P14  1  0.662  0.336  0.816  1.0
  P  P15  1  0.336  0.662  0.316  1.0
  P  P16  1  0.609  0.803  0.896  1.0
  P  P17  1  0.196  0.393  0.908  1.0
  P  P18  1  0.195  0.799  0.903  1.0
  P  P19  1  0.393  0.196  0.408  1.0
  P  P20  1  0.803  0.609  0.396  1.0
  P  P21  1  0.799  0.195  0.403  1.0
[/CIF]
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The material structure described by Na4Sr2SiP4 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 Sr sites. In the first Sr site, Sr(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 Sr site, Sr(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 Sr(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 Sr(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 Sr(1), two equivalent Sr(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 Sr(1), two equivalent Sr(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 Sr(1), two equivalent Sr(2), and one Si(1) atom. is represented by the CIF card [CIF]
data_Na4Sr2SiP4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.253
_cell_length_b   9.253
_cell_length_c   7.286
_cell_angle_alpha   89.730
_cell_angle_beta   89.730
_cell_angle_gamma   119.978
_symmetry_Int_Tables_number   1
_cell_volume   540.360
_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  0.055  0.527  0.611  1.0
  Na  Na1  1  0.527  0.055  0.111  1.0
  Na  Na2  1  0.277  0.135  0.808  1.0
  Na  Na3  1  0.867  0.714  0.778  1.0
  Na  Na4  1  0.862  0.151  0.788  1.0
  Na  Na5  1  0.714  0.867  0.278  1.0
  Na  Na6  1  0.135  0.277  0.308  1.0
  Na  Na7  1  0.151  0.862  0.288  1.0
  Sr  Sr8  1  0.471  0.949  0.614  1.0
  Sr  Sr9  1  0.468  0.521  0.615  1.0
  Sr  Sr10  1  0.949  0.471  0.114  1.0
  Sr  Sr11  1  0.521  0.468  0.115  1.0
  Si  Si12  1  0.672  0.337  0.499  1.0
  Si  Si13  1  0.337  0.672  0.999  1.0
  P  P14  1  0.662  0.336  0.816  1.0
  P  P15  1  0.336  0.662  0.316  1.0
  P  P16  1  0.609  0.803  0.896  1.0
  P  P17  1  0.196  0.393  0.908  1.0
  P  P18  1  0.195  0.799  0.903  1.0
  P  P19  1  0.393  0.196  0.408  1.0
  P  P20  1  0.803  0.609  0.396  1.0
  P  P21  1  0.799  0.195  0.403  1.0
[/CIF]
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