The structure described by Na4Eu2SiAs4 is alpha Pu-derived structured and 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 As(1), one As(2), one As(3), and two equivalent As(4) atoms. In the second Na site, Na(2) is bonded in a 4-coordinate geometry to one As(1), one As(4), and two equivalent As(3) atoms. In the third Na site, Na(3) is bonded in a 4-coordinate geometry to one As(1), one As(4), and two equivalent As(2) atoms. In the fourth Na site, Na(4) is bonded in a 4-coordinate geometry to one As(1), one As(2), one As(3), and one As(4) atom. There are two inequivalent Eu sites. In the first Eu site, Eu(1) is bonded in a 5-coordinate geometry to one As(1), one As(2), one As(3), and two equivalent As(4) atoms. In the second Eu site, Eu(2) is bonded in a 5-coordinate geometry to one As(1), two equivalent As(2), and two equivalent As(3) atoms. Si(1) is bonded in a distorted tetrahedral geometry to one Na(1), one As(1), one As(2), one As(3), and one As(4) atom. There are four inequivalent As sites. In the first As site, As(4) is bonded in a 8-coordinate geometry to one Na(2), one Na(3), one Na(4), two equivalent Na(1), two equivalent Eu(1), and one Si(1) atom. In the second As site, As(1) is bonded in a 7-coordinate geometry to one Na(1), one Na(2), one Na(3), one Na(4), one Eu(1), one Eu(2), and one Si(1) atom. In the third As site, As(2) is bonded in a 8-coordinate geometry to one Na(1), one Na(4), two equivalent Na(3), one Eu(1), two equivalent Eu(2), and one Si(1) atom. In the fourth As site, As(3) is bonded in a 8-coordinate geometry to one Na(1), one Na(4), two equivalent Na(2), one Eu(1), two equivalent Eu(2), and one Si(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na4Eu2SiAs4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.442
_cell_length_b   9.442
_cell_length_c   7.307
_cell_angle_alpha   89.322
_cell_angle_beta   89.322
_cell_angle_gamma   119.800
_symmetry_Int_Tables_number   1
_cell_volume   565.170
_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  0.475  0.945  0.384  1.0
  Na  Na1  1  0.945  0.475  0.884  1.0
  Na  Na2  1  0.865  0.723  0.174  1.0
  Na  Na3  1  0.286  0.133  0.220  1.0
  Na  Na4  1  0.849  0.140  0.203  1.0
  Na  Na5  1  0.133  0.286  0.720  1.0
  Na  Na6  1  0.723  0.865  0.674  1.0
  Na  Na7  1  0.140  0.849  0.703  1.0
  Eu  Eu8  1  0.048  0.527  0.381  1.0
  Eu  Eu9  1  0.482  0.529  0.378  1.0
  Eu  Eu10  1  0.527  0.048  0.881  1.0
  Eu  Eu11  1  0.529  0.482  0.878  1.0
  Si  Si12  1  0.663  0.329  0.498  1.0
  Si  Si13  1  0.329  0.663  0.998  1.0
  As  As14  1  0.661  0.336  0.167  1.0
  As  As15  1  0.336  0.661  0.667  1.0
  As  As16  1  0.196  0.386  0.110  1.0
  As  As17  1  0.614  0.807  0.087  1.0
  As  As18  1  0.199  0.808  0.097  1.0
  As  As19  1  0.807  0.614  0.587  1.0
  As  As20  1  0.386  0.196  0.610  1.0
  As  As21  1  0.808  0.199  0.597  1.0
[/CIF]
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The structure described by Na4Eu2SiAs4 is alpha Pu-derived structured and 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 As(1), one As(2), one As(3), and two equivalent As(4) atoms. In the second Na site, Na(2) is bonded in a 4-coordinate geometry to one As(1), one As(4), and two equivalent As(3) atoms. In the third Na site, Na(3) is bonded in a 4-coordinate geometry to one As(1), one As(4), and two equivalent As(2) atoms. In the fourth Na site, Na(4) is bonded in a 4-coordinate geometry to one As(1), one As(2), one As(3), and one As(4) atom. There are two inequivalent Eu sites. In the first Eu site, Eu(1) is bonded in a 5-coordinate geometry to one As(1), one As(2), one As(3), and two equivalent As(4) atoms. In the second Eu site, Eu(2) is bonded in a 5-coordinate geometry to one As(1), two equivalent As(2), and two equivalent As(3) atoms. Si(1) is bonded in a distorted tetrahedral geometry to one Na(1), one As(1), one As(2), one As(3), and one As(4) atom. There are four inequivalent As sites. In the first As site, As(4) is bonded in a 8-coordinate geometry to one Na(2), one Na(3), one Na(4), two equivalent Na(1), two equivalent Eu(1), and one Si(1) atom. In the second As site, As(1) is bonded in a 7-coordinate geometry to one Na(1), one Na(2), one Na(3), one Na(4), one Eu(1), one Eu(2), and one Si(1) atom. In the third As site, As(2) is bonded in a 8-coordinate geometry to one Na(1), one Na(4), two equivalent Na(3), one Eu(1), two equivalent Eu(2), and one Si(1) atom. In the fourth As site, As(3) is bonded in a 8-coordinate geometry to one Na(1), one Na(4), two equivalent Na(2), one Eu(1), two equivalent Eu(2), and one Si(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na4Eu2SiAs4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.442
_cell_length_b   9.442
_cell_length_c   7.307
_cell_angle_alpha   89.322
_cell_angle_beta   89.322
_cell_angle_gamma   119.800
_symmetry_Int_Tables_number   1
_cell_volume   565.170
_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  0.475  0.945  0.384  1.0
  Na  Na1  1  0.945  0.475  0.884  1.0
  Na  Na2  1  0.865  0.723  0.174  1.0
  Na  Na3  1  0.286  0.133  0.220  1.0
  Na  Na4  1  0.849  0.140  0.203  1.0
  Na  Na5  1  0.133  0.286  0.720  1.0
  Na  Na6  1  0.723  0.865  0.674  1.0
  Na  Na7  1  0.140  0.849  0.703  1.0
  Eu  Eu8  1  0.048  0.527  0.381  1.0
  Eu  Eu9  1  0.482  0.529  0.378  1.0
  Eu  Eu10  1  0.527  0.048  0.881  1.0
  Eu  Eu11  1  0.529  0.482  0.878  1.0
  Si  Si12  1  0.663  0.329  0.498  1.0
  Si  Si13  1  0.329  0.663  0.998  1.0
  As  As14  1  0.661  0.336  0.167  1.0
  As  As15  1  0.336  0.661  0.667  1.0
  As  As16  1  0.196  0.386  0.110  1.0
  As  As17  1  0.614  0.807  0.087  1.0
  As  As18  1  0.199  0.808  0.097  1.0
  As  As19  1  0.807  0.614  0.587  1.0
  As  As20  1  0.386  0.196  0.610  1.0
  As  As21  1  0.808  0.199  0.597  1.0
[/CIF]
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