The crystal structure described by Na4MgCu(AsO4)2 crystallizes in the triclinic P1 space group. There are four inequivalent Na sites. In the first Na site, Na(1) is bonded in a distorted rectangular see-saw-like geometry to one O(2), one O(3), one O(5), and one O(6) atom. In the second Na site, Na(2) is bonded in a 4-coordinate geometry to one O(3), one O(4), one O(5), and one O(7) atom. In the third Na site, Na(3) is bonded in a 5-coordinate geometry to one O(1), one O(4), one O(6), one O(7), and one O(8) atom. In the fourth Na site, Na(4) is bonded in a 6-coordinate geometry to one O(1), one O(4), one O(6), one O(7), and two equivalent O(8) atoms. Mg(1) is bonded to one O(1), one O(2), one O(5), one O(6), and one O(8) atom to form MgO5 trigonal bipyramids that share  a cornercorner with one As(1)O4 tetrahedra. Cu(1) is bonded in a linear geometry to one O(2) and one O(4) atom. There are two inequivalent As sites. In the first As site, As(1) is bonded to one O(3), one O(4), one O(7), and one O(8) atom to form AsO4 tetrahedra that share  a cornercorner with one Mg(1)O5 trigonal bipyramid. In the second As site, As(2) is bonded in a 4-coordinate geometry to one O(1), one O(2), one O(5), and one O(6) atom. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Na(3), one Na(4), one Mg(1), and one As(2) atom. In the second O site, O(2) is bonded in a distorted tetrahedral geometry to one Na(1), one Mg(1), one Cu(1), and one As(2) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Na(1), one Na(2), and one As(1) atom. In the fourth O site, O(4) is bonded in a 5-coordinate geometry to one Na(2), one Na(3), one Na(4), one Cu(1), and one As(1) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Na(1), one Na(2), one Mg(1), and one As(2) atom. In the sixth O site, O(6) is bonded in a 5-coordinate geometry to one Na(1), one Na(3), one Na(4), one Mg(1), and one As(2) atom. In the seventh O site, O(7) is bonded in a distorted trigonal pyramidal geometry to one Na(2), one Na(3), one Na(4), and one As(1) atom. In the eighth O site, O(8) is bonded in a 5-coordinate geometry to one Na(3), two equivalent Na(4), one Mg(1), and one As(1) atom. is represented by the CIF card [CIF]
data_Na4MgCu(AsO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.415
_cell_length_b   5.588
_cell_length_c   9.068
_cell_angle_alpha   78.410
_cell_angle_beta   108.171
_cell_angle_gamma   119.178
_symmetry_Int_Tables_number   1
_cell_volume   227.250
_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  0.381  0.578  0.127  1.0
  Na  Na1  1  0.746  0.433  0.901  1.0
  Na  Na2  1  0.979  0.206  0.584  1.0
  Na  Na3  1  0.622  0.557  0.520  1.0
  Mg  Mg4  1  0.142  0.884  0.320  1.0
  Cu  Cu5  1  0.012  0.000  0.927  1.0
  As  As6  1  0.377  0.835  0.715  1.0
  As  As7  1  0.687  0.188  0.234  1.0
  O  O8  1  0.567  0.207  0.390  1.0
  O  O9  1  0.253  0.112  0.113  1.0
  O  O10  1  0.218  0.622  0.858  1.0
  O  O11  1  0.724  0.847  0.746  1.0
  O  O12  1  0.986  0.520  0.215  1.0
  O  O13  1  0.806  0.930  0.330  1.0
  O  O14  1  0.415  0.160  0.703  1.0
  O  O15  1  0.184  0.680  0.540  1.0
[/CIF]
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The crystal structure described by Na4MgCu(AsO4)2 crystallizes in the triclinic P1 space group. There are four inequivalent Na sites. In the first Na site, Na(1) is bonded in a distorted rectangular see-saw-like geometry to one O(2), one O(3), one O(5), and one O(6) atom. In the second Na site, Na(2) is bonded in a 4-coordinate geometry to one O(3), one O(4), one O(5), and one O(7) atom. In the third Na site, Na(3) is bonded in a 5-coordinate geometry to one O(1), one O(4), one O(6), one O(7), and one O(8) atom. In the fourth Na site, Na(4) is bonded in a 6-coordinate geometry to one O(1), one O(4), one O(6), one O(7), and two equivalent O(8) atoms. Mg(1) is bonded to one O(1), one O(2), one O(5), one O(6), and one O(8) atom to form MgO5 trigonal bipyramids that share  a cornercorner with one As(1)O4 tetrahedra. Cu(1) is bonded in a linear geometry to one O(2) and one O(4) atom. There are two inequivalent As sites. In the first As site, As(1) is bonded to one O(3), one O(4), one O(7), and one O(8) atom to form AsO4 tetrahedra that share  a cornercorner with one Mg(1)O5 trigonal bipyramid. In the second As site, As(2) is bonded in a 4-coordinate geometry to one O(1), one O(2), one O(5), and one O(6) atom. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Na(3), one Na(4), one Mg(1), and one As(2) atom. In the second O site, O(2) is bonded in a distorted tetrahedral geometry to one Na(1), one Mg(1), one Cu(1), and one As(2) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Na(1), one Na(2), and one As(1) atom. In the fourth O site, O(4) is bonded in a 5-coordinate geometry to one Na(2), one Na(3), one Na(4), one Cu(1), and one As(1) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Na(1), one Na(2), one Mg(1), and one As(2) atom. In the sixth O site, O(6) is bonded in a 5-coordinate geometry to one Na(1), one Na(3), one Na(4), one Mg(1), and one As(2) atom. In the seventh O site, O(7) is bonded in a distorted trigonal pyramidal geometry to one Na(2), one Na(3), one Na(4), and one As(1) atom. In the eighth O site, O(8) is bonded in a 5-coordinate geometry to one Na(3), two equivalent Na(4), one Mg(1), and one As(1) atom. is represented by the CIF card [CIF]
data_Na4MgCu(AsO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.415
_cell_length_b   5.588
_cell_length_c   9.068
_cell_angle_alpha   78.410
_cell_angle_beta   108.171
_cell_angle_gamma   119.178
_symmetry_Int_Tables_number   1
_cell_volume   227.250
_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  0.381  0.578  0.127  1.0
  Na  Na1  1  0.746  0.433  0.901  1.0
  Na  Na2  1  0.979  0.206  0.584  1.0
  Na  Na3  1  0.622  0.557  0.520  1.0
  Mg  Mg4  1  0.142  0.884  0.320  1.0
  Cu  Cu5  1  0.012  0.000  0.927  1.0
  As  As6  1  0.377  0.835  0.715  1.0
  As  As7  1  0.687  0.188  0.234  1.0
  O  O8  1  0.567  0.207  0.390  1.0
  O  O9  1  0.253  0.112  0.113  1.0
  O  O10  1  0.218  0.622  0.858  1.0
  O  O11  1  0.724  0.847  0.746  1.0
  O  O12  1  0.986  0.520  0.215  1.0
  O  O13  1  0.806  0.930  0.330  1.0
  O  O14  1  0.415  0.160  0.703  1.0
  O  O15  1  0.184  0.680  0.540  1.0
[/CIF]
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