The structure described by Na4Cr2As(CO4)4 crystallizes in the orthorhombic Fddd space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms to form distorted NaO6 octahedra that share corners with four equivalent Na(2)O6 octahedra, edges with two equivalent Cr(1)O6 octahedra, and  an edgeedge with one As(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 57-87°. In the second Na site, Na(2) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form distorted NaO6 octahedra that share corners with four equivalent Na(1)O6 octahedra, edges with two equivalent Cr(1)O6 octahedra, and  an edgeedge with one As(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 57-87°. Cr(1) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form CrO6 octahedra that share edges with two equivalent Na(1)O6 octahedra and edges with two equivalent Na(2)O6 octahedra. C(1) is bonded in a trigonal planar geometry to one O(1), one O(3), and one O(4) atom. As(1) is bonded to four equivalent O(2) atoms to form AsO4 tetrahedra that share edges with two equivalent Na(1)O6 octahedra and edges with two equivalent Na(2)O6 octahedra. There are four inequivalent O sites. In the first O site, O(2) is bonded in a distorted T-shaped geometry to one Na(1), one Na(2), and one As(1) atom. In the second O site, O(3) is bonded in a 3-coordinate geometry to one Na(2), one Cr(1), and one C(1) atom. In the third O site, O(1) is bonded in a 3-coordinate geometry to one Na(1), one Cr(1), and one C(1) atom. In the fourth O site, O(4) is bonded in a distorted rectangular see-saw-like geometry to one Na(1), one Na(2), one Cr(1), and one C(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na4Cr2As(CO4)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.962
_cell_length_b   9.823
_cell_length_c   9.962
_cell_angle_alpha   60.760
_cell_angle_beta   92.103
_cell_angle_gamma   60.760
_symmetry_Int_Tables_number   1
_cell_volume   692.039
_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  0.089  0.823  0.839  1.0
  Na  Na1  1  0.088  0.250  0.838  1.0
  Na  Na2  1  0.338  0.750  0.588  1.0
  Na  Na3  1  0.339  0.323  0.589  1.0
  Na  Na4  1  0.661  0.677  0.411  1.0
  Na  Na5  1  0.662  0.250  0.412  1.0
  Na  Na6  1  0.912  0.750  0.162  1.0
  Na  Na7  1  0.911  0.177  0.161  1.0
  Cr  Cr8  1  0.000  0.500  0.000  1.0
  Cr  Cr9  1  0.500  0.000  0.500  1.0
  Cr  Cr10  1  0.500  0.500  0.000  1.0
  Cr  Cr11  1  0.500  0.000  0.000  1.0
  As  As12  1  0.125  0.750  0.375  1.0
  As  As13  1  0.875  0.250  0.625  1.0
  C  C14  1  0.365  0.924  0.783  1.0
  C  C15  1  0.283  0.424  0.865  1.0
  C  C16  1  0.711  0.924  0.793  1.0
  C  C17  1  0.707  0.576  0.789  1.0
  C  C18  1  0.293  0.424  0.211  1.0
  C  C19  1  0.289  0.076  0.207  1.0
  C  C20  1  0.717  0.576  0.135  1.0
  C  C21  1  0.635  0.076  0.217  1.0
  O  O22  1  0.359  0.786  0.893  1.0
  O  O23  1  0.060  0.898  0.440  1.0
  O  O24  1  0.368  0.950  0.643  1.0
  O  O25  1  0.143  0.450  0.868  1.0
  O  O26  1  0.682  0.950  0.907  1.0
  O  O27  1  0.310  0.544  0.859  1.0
  O  O28  1  0.042  0.898  0.163  1.0
  O  O29  1  0.060  0.602  0.440  1.0
  O  O30  1  0.403  0.956  0.354  1.0
  O  O31  1  0.593  0.550  0.818  1.0
  O  O32  1  0.393  0.286  0.859  1.0
  O  O33  1  0.337  0.602  0.458  1.0
  O  O34  1  0.855  0.786  0.821  1.0
  O  O35  1  0.679  0.714  0.645  1.0
  O  O36  1  0.359  0.044  0.810  1.0
  O  O37  1  0.146  0.544  0.097  1.0
  O  O38  1  0.854  0.456  0.903  1.0
  O  O39  1  0.641  0.956  0.190  1.0
  O  O40  1  0.321  0.286  0.355  1.0
  O  O41  1  0.145  0.214  0.179  1.0
  O  O42  1  0.663  0.398  0.542  1.0
  O  O43  1  0.607  0.714  0.141  1.0
  O  O44  1  0.407  0.450  0.182  1.0
  O  O45  1  0.597  0.044  0.646  1.0
  O  O46  1  0.940  0.398  0.560  1.0
  O  O47  1  0.958  0.102  0.837  1.0
  O  O48  1  0.690  0.456  0.141  1.0
  O  O49  1  0.318  0.050  0.093  1.0
  O  O50  1  0.857  0.550  0.132  1.0
  O  O51  1  0.632  0.050  0.357  1.0
  O  O52  1  0.940  0.102  0.560  1.0
  O  O53  1  0.641  0.214  0.107  1.0
[/CIF]
.
The structure described by Na4Cr2As(CO4)4 crystallizes in the orthorhombic Fddd space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms to form distorted NaO6 octahedra that share corners with four equivalent Na(2)O6 octahedra, edges with two equivalent Cr(1)O6 octahedra, and  an edgeedge with one As(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 57-87°. In the second Na site, Na(2) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form distorted NaO6 octahedra that share corners with four equivalent Na(1)O6 octahedra, edges with two equivalent Cr(1)O6 octahedra, and  an edgeedge with one As(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 57-87°. Cr(1) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form CrO6 octahedra that share edges with two equivalent Na(1)O6 octahedra and edges with two equivalent Na(2)O6 octahedra. C(1) is bonded in a trigonal planar geometry to one O(1), one O(3), and one O(4) atom. As(1) is bonded to four equivalent O(2) atoms to form AsO4 tetrahedra that share edges with two equivalent Na(1)O6 octahedra and edges with two equivalent Na(2)O6 octahedra. There are four inequivalent O sites. In the first O site, O(2) is bonded in a distorted T-shaped geometry to one Na(1), one Na(2), and one As(1) atom. In the second O site, O(3) is bonded in a 3-coordinate geometry to one Na(2), one Cr(1), and one C(1) atom. In the third O site, O(1) is bonded in a 3-coordinate geometry to one Na(1), one Cr(1), and one C(1) atom. In the fourth O site, O(4) is bonded in a distorted rectangular see-saw-like geometry to one Na(1), one Na(2), one Cr(1), and one C(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na4Cr2As(CO4)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.962
_cell_length_b   9.823
_cell_length_c   9.962
_cell_angle_alpha   60.760
_cell_angle_beta   92.103
_cell_angle_gamma   60.760
_symmetry_Int_Tables_number   1
_cell_volume   692.039
_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  0.089  0.823  0.839  1.0
  Na  Na1  1  0.088  0.250  0.838  1.0
  Na  Na2  1  0.338  0.750  0.588  1.0
  Na  Na3  1  0.339  0.323  0.589  1.0
  Na  Na4  1  0.661  0.677  0.411  1.0
  Na  Na5  1  0.662  0.250  0.412  1.0
  Na  Na6  1  0.912  0.750  0.162  1.0
  Na  Na7  1  0.911  0.177  0.161  1.0
  Cr  Cr8  1  0.000  0.500  0.000  1.0
  Cr  Cr9  1  0.500  0.000  0.500  1.0
  Cr  Cr10  1  0.500  0.500  0.000  1.0
  Cr  Cr11  1  0.500  0.000  0.000  1.0
  As  As12  1  0.125  0.750  0.375  1.0
  As  As13  1  0.875  0.250  0.625  1.0
  C  C14  1  0.365  0.924  0.783  1.0
  C  C15  1  0.283  0.424  0.865  1.0
  C  C16  1  0.711  0.924  0.793  1.0
  C  C17  1  0.707  0.576  0.789  1.0
  C  C18  1  0.293  0.424  0.211  1.0
  C  C19  1  0.289  0.076  0.207  1.0
  C  C20  1  0.717  0.576  0.135  1.0
  C  C21  1  0.635  0.076  0.217  1.0
  O  O22  1  0.359  0.786  0.893  1.0
  O  O23  1  0.060  0.898  0.440  1.0
  O  O24  1  0.368  0.950  0.643  1.0
  O  O25  1  0.143  0.450  0.868  1.0
  O  O26  1  0.682  0.950  0.907  1.0
  O  O27  1  0.310  0.544  0.859  1.0
  O  O28  1  0.042  0.898  0.163  1.0
  O  O29  1  0.060  0.602  0.440  1.0
  O  O30  1  0.403  0.956  0.354  1.0
  O  O31  1  0.593  0.550  0.818  1.0
  O  O32  1  0.393  0.286  0.859  1.0
  O  O33  1  0.337  0.602  0.458  1.0
  O  O34  1  0.855  0.786  0.821  1.0
  O  O35  1  0.679  0.714  0.645  1.0
  O  O36  1  0.359  0.044  0.810  1.0
  O  O37  1  0.146  0.544  0.097  1.0
  O  O38  1  0.854  0.456  0.903  1.0
  O  O39  1  0.641  0.956  0.190  1.0
  O  O40  1  0.321  0.286  0.355  1.0
  O  O41  1  0.145  0.214  0.179  1.0
  O  O42  1  0.663  0.398  0.542  1.0
  O  O43  1  0.607  0.714  0.141  1.0
  O  O44  1  0.407  0.450  0.182  1.0
  O  O45  1  0.597  0.044  0.646  1.0
  O  O46  1  0.940  0.398  0.560  1.0
  O  O47  1  0.958  0.102  0.837  1.0
  O  O48  1  0.690  0.456  0.141  1.0
  O  O49  1  0.318  0.050  0.093  1.0
  O  O50  1  0.857  0.550  0.132  1.0
  O  O51  1  0.632  0.050  0.357  1.0
  O  O52  1  0.940  0.102  0.560  1.0
  O  O53  1  0.641  0.214  0.107  1.0
[/CIF]
.