The structure described by Na2Zn3GeAs4 crystallizes in the monoclinic Cm space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded to one As(1), one As(3), two equivalent As(2), and two equivalent As(4) atoms to form distorted NaAs6 octahedra that share  a cornercorner with one Zn(1)As4 tetrahedra, corners with five equivalent Ge(1)As4 tetrahedra, edges with two equivalent Na(1)As6 octahedra,  an edgeedge with one Ge(1)As4 tetrahedra, and edges with two equivalent Zn(1)As4 tetrahedra. In the second Na site, Na(2) is bonded in a 6-coordinate geometry to one As(2), one As(4), two equivalent As(1), and two equivalent As(3) atoms. There are three inequivalent Zn sites. In the first Zn site, Zn(1) is bonded to one As(1), one As(4), and two equivalent As(3) atoms to form distorted ZnAs4 tetrahedra that share  a cornercorner with one Na(1)As6 octahedra, corners with two equivalent Zn(1)As4 tetrahedra, corners with four equivalent Ge(1)As4 tetrahedra, and edges with two equivalent Na(1)As6 octahedra. The corner-sharing octahedral tilt angles are 54°. In the second Zn site, Zn(2) is bonded in a 4-coordinate geometry to one As(1), one As(4), and two equivalent As(2) atoms. In the third Zn site, Zn(3) is bonded in a 4-coordinate geometry to one As(2), one As(3), and two equivalent As(1) atoms. Ge(1) is bonded to one As(2), one As(3), and two equivalent As(4) atoms to form GeAs4 tetrahedra that share corners with five equivalent Na(1)As6 octahedra, corners with two equivalent Ge(1)As4 tetrahedra, corners with four equivalent Zn(1)As4 tetrahedra, and  an edgeedge with one Na(1)As6 octahedra. The corner-sharing octahedral tilt angles range from 22-49°. There are four inequivalent As sites. In the first As site, As(1) is bonded to one Na(1), two equivalent Na(2), one Zn(1), one Zn(2), and two equivalent Zn(3) atoms to form distorted edge-sharing AsNa3Zn4 pentagonal bipyramids. In the second As site, As(2) is bonded in a 7-coordinate geometry to one Na(2), two equivalent Na(1), one Zn(3), two equivalent Zn(2), and one Ge(1) atom. In the third As site, As(3) is bonded in a 7-coordinate geometry to one Na(1), two equivalent Na(2), one Zn(3), two equivalent Zn(1), and one Ge(1) atom. In the fourth As site, As(4) is bonded in a 7-coordinate geometry to one Na(2), two equivalent Na(1), one Zn(1), one Zn(2), and two equivalent Ge(1) atoms. is represented by the CIF file [CIF]
data_Na2Zn3GeAs4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.583
_cell_length_b   8.583
_cell_length_c   7.179
_cell_angle_alpha   65.506
_cell_angle_beta   65.506
_cell_angle_gamma   27.852
_symmetry_Int_Tables_number   1
_cell_volume   223.394
_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  0.508  0.508  0.492  1.0
  Na  Na1  1  0.004  0.004  0.994  1.0
  Zn  Zn2  1  0.803  0.803  0.518  1.0
  Zn  Zn3  1  0.672  0.672  0.979  1.0
  Zn  Zn4  1  0.181  0.181  0.500  1.0
  Ge  Ge5  1  0.313  0.313  0.030  1.0
  As  As6  1  0.628  0.628  0.699  1.0
  As  As7  1  0.147  0.147  0.190  1.0
  As  As8  1  0.370  0.370  0.302  1.0
  As  As9  1  0.867  0.867  0.795  1.0
[/CIF]
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The structure described by Na2Zn3GeAs4 crystallizes in the monoclinic Cm space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded to one As(1), one As(3), two equivalent As(2), and two equivalent As(4) atoms to form distorted NaAs6 octahedra that share  a cornercorner with one Zn(1)As4 tetrahedra, corners with five equivalent Ge(1)As4 tetrahedra, edges with two equivalent Na(1)As6 octahedra,  an edgeedge with one Ge(1)As4 tetrahedra, and edges with two equivalent Zn(1)As4 tetrahedra. In the second Na site, Na(2) is bonded in a 6-coordinate geometry to one As(2), one As(4), two equivalent As(1), and two equivalent As(3) atoms. There are three inequivalent Zn sites. In the first Zn site, Zn(1) is bonded to one As(1), one As(4), and two equivalent As(3) atoms to form distorted ZnAs4 tetrahedra that share  a cornercorner with one Na(1)As6 octahedra, corners with two equivalent Zn(1)As4 tetrahedra, corners with four equivalent Ge(1)As4 tetrahedra, and edges with two equivalent Na(1)As6 octahedra. The corner-sharing octahedral tilt angles are 54°. In the second Zn site, Zn(2) is bonded in a 4-coordinate geometry to one As(1), one As(4), and two equivalent As(2) atoms. In the third Zn site, Zn(3) is bonded in a 4-coordinate geometry to one As(2), one As(3), and two equivalent As(1) atoms. Ge(1) is bonded to one As(2), one As(3), and two equivalent As(4) atoms to form GeAs4 tetrahedra that share corners with five equivalent Na(1)As6 octahedra, corners with two equivalent Ge(1)As4 tetrahedra, corners with four equivalent Zn(1)As4 tetrahedra, and  an edgeedge with one Na(1)As6 octahedra. The corner-sharing octahedral tilt angles range from 22-49°. There are four inequivalent As sites. In the first As site, As(1) is bonded to one Na(1), two equivalent Na(2), one Zn(1), one Zn(2), and two equivalent Zn(3) atoms to form distorted edge-sharing AsNa3Zn4 pentagonal bipyramids. In the second As site, As(2) is bonded in a 7-coordinate geometry to one Na(2), two equivalent Na(1), one Zn(3), two equivalent Zn(2), and one Ge(1) atom. In the third As site, As(3) is bonded in a 7-coordinate geometry to one Na(1), two equivalent Na(2), one Zn(3), two equivalent Zn(1), and one Ge(1) atom. In the fourth As site, As(4) is bonded in a 7-coordinate geometry to one Na(2), two equivalent Na(1), one Zn(1), one Zn(2), and two equivalent Ge(1) atoms. is represented by the CIF file [CIF]
data_Na2Zn3GeAs4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.583
_cell_length_b   8.583
_cell_length_c   7.179
_cell_angle_alpha   65.506
_cell_angle_beta   65.506
_cell_angle_gamma   27.852
_symmetry_Int_Tables_number   1
_cell_volume   223.394
_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  0.508  0.508  0.492  1.0
  Na  Na1  1  0.004  0.004  0.994  1.0
  Zn  Zn2  1  0.803  0.803  0.518  1.0
  Zn  Zn3  1  0.672  0.672  0.979  1.0
  Zn  Zn4  1  0.181  0.181  0.500  1.0
  Ge  Ge5  1  0.313  0.313  0.030  1.0
  As  As6  1  0.628  0.628  0.699  1.0
  As  As7  1  0.147  0.147  0.190  1.0
  As  As8  1  0.370  0.370  0.302  1.0
  As  As9  1  0.867  0.867  0.795  1.0
[/CIF]
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