The material structure described by Mg3Zn3As4 crystallizes in the monoclinic Cm space group. There are three inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 4-coordinate geometry to one Zn(1), one As(2), one As(3), and two equivalent As(4) atoms. In the second Mg site, Mg(2) is bonded in a 4-coordinate geometry to two equivalent Zn(1), one As(1), one As(4), and two equivalent As(3) atoms. In the third Mg site, Mg(3) is bonded to one As(1), one As(4), and two equivalent As(2) atoms to form distorted MgAs4 tetrahedra that share  a cornercorner with one Zn(2)As6 octahedra, corners with five equivalent Zn(3)As6 octahedra, corners with two equivalent Mg(3)As4 tetrahedra,  an edgeedge with one Zn(3)As6 octahedra, and edges with two equivalent Zn(2)As6 octahedra. The corner-sharing octahedral tilt angles range from 15-59°. There are three inequivalent Zn sites. In the first Zn site, Zn(1) is bonded in a 7-coordinate geometry to one Mg(1), two equivalent Mg(2), one As(2), one As(3), and two equivalent As(1) atoms. In the second Zn site, Zn(2) is bonded to one As(2), one As(4), two equivalent As(1), and two equivalent As(3) atoms to form distorted ZnAs6 octahedra that share  a cornercorner with one Mg(3)As4 tetrahedra, edges with two equivalent Zn(2)As6 octahedra, edges with four equivalent Zn(3)As6 octahedra, and edges with two equivalent Mg(3)As4 tetrahedra. In the third Zn site, Zn(3) is bonded to one As(1), one As(3), two equivalent As(2), and two equivalent As(4) atoms to form ZnAs6 octahedra that share corners with five equivalent Mg(3)As4 tetrahedra, edges with two equivalent Zn(3)As6 octahedra, edges with four equivalent Zn(2)As6 octahedra, and  an edgeedge with one Mg(3)As4 tetrahedra. There are four inequivalent As sites. In the first As site, As(1) is bonded in a 7-coordinate geometry to one Mg(2), one Mg(3), one Zn(3), two equivalent Zn(1), and two equivalent Zn(2) atoms. In the second As site, As(2) is bonded in a 7-coordinate geometry to one Mg(1), two equivalent Mg(3), one Zn(1), one Zn(2), and two equivalent Zn(3) atoms. In the third As site, As(3) is bonded in a 7-coordinate geometry to one Mg(1), two equivalent Mg(2), one Zn(1), one Zn(3), and two equivalent Zn(2) atoms. In the fourth As site, As(4) is bonded in a 7-coordinate geometry to one Mg(2), one Mg(3), two equivalent Mg(1), one Zn(2), and two equivalent Zn(3) atoms. is represented by the CIF card [CIF]
data_Mg3Zn3As4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.798
_cell_length_b   7.798
_cell_length_c   7.253
_cell_angle_alpha   63.312
_cell_angle_beta   63.312
_cell_angle_gamma   31.658
_symmetry_Int_Tables_number   1
_cell_volume   204.714
_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
  Mg  Mg0  1  0.683  0.683  0.982  1.0
  Mg  Mg1  1  0.181  0.181  0.491  1.0
  Mg  Mg2  1  0.331  0.331  0.005  1.0
  Zn  Zn3  1  0.810  0.810  0.521  1.0
  Zn  Zn4  1  0.010  0.010  0.996  1.0
  Zn  Zn5  1  0.499  0.499  0.499  1.0
  As  As6  1  0.386  0.386  0.304  1.0
  As  As7  1  0.889  0.889  0.762  1.0
  As  As8  1  0.604  0.604  0.727  1.0
  As  As9  1  0.116  0.116  0.214  1.0
[/CIF]
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The material structure described by Mg3Zn3As4 crystallizes in the monoclinic Cm space group. There are three inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 4-coordinate geometry to one Zn(1), one As(2), one As(3), and two equivalent As(4) atoms. In the second Mg site, Mg(2) is bonded in a 4-coordinate geometry to two equivalent Zn(1), one As(1), one As(4), and two equivalent As(3) atoms. In the third Mg site, Mg(3) is bonded to one As(1), one As(4), and two equivalent As(2) atoms to form distorted MgAs4 tetrahedra that share  a cornercorner with one Zn(2)As6 octahedra, corners with five equivalent Zn(3)As6 octahedra, corners with two equivalent Mg(3)As4 tetrahedra,  an edgeedge with one Zn(3)As6 octahedra, and edges with two equivalent Zn(2)As6 octahedra. The corner-sharing octahedral tilt angles range from 15-59°. There are three inequivalent Zn sites. In the first Zn site, Zn(1) is bonded in a 7-coordinate geometry to one Mg(1), two equivalent Mg(2), one As(2), one As(3), and two equivalent As(1) atoms. In the second Zn site, Zn(2) is bonded to one As(2), one As(4), two equivalent As(1), and two equivalent As(3) atoms to form distorted ZnAs6 octahedra that share  a cornercorner with one Mg(3)As4 tetrahedra, edges with two equivalent Zn(2)As6 octahedra, edges with four equivalent Zn(3)As6 octahedra, and edges with two equivalent Mg(3)As4 tetrahedra. In the third Zn site, Zn(3) is bonded to one As(1), one As(3), two equivalent As(2), and two equivalent As(4) atoms to form ZnAs6 octahedra that share corners with five equivalent Mg(3)As4 tetrahedra, edges with two equivalent Zn(3)As6 octahedra, edges with four equivalent Zn(2)As6 octahedra, and  an edgeedge with one Mg(3)As4 tetrahedra. There are four inequivalent As sites. In the first As site, As(1) is bonded in a 7-coordinate geometry to one Mg(2), one Mg(3), one Zn(3), two equivalent Zn(1), and two equivalent Zn(2) atoms. In the second As site, As(2) is bonded in a 7-coordinate geometry to one Mg(1), two equivalent Mg(3), one Zn(1), one Zn(2), and two equivalent Zn(3) atoms. In the third As site, As(3) is bonded in a 7-coordinate geometry to one Mg(1), two equivalent Mg(2), one Zn(1), one Zn(3), and two equivalent Zn(2) atoms. In the fourth As site, As(4) is bonded in a 7-coordinate geometry to one Mg(2), one Mg(3), two equivalent Mg(1), one Zn(2), and two equivalent Zn(3) atoms. is represented by the CIF card [CIF]
data_Mg3Zn3As4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.798
_cell_length_b   7.798
_cell_length_c   7.253
_cell_angle_alpha   63.312
_cell_angle_beta   63.312
_cell_angle_gamma   31.658
_symmetry_Int_Tables_number   1
_cell_volume   204.714
_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
  Mg  Mg0  1  0.683  0.683  0.982  1.0
  Mg  Mg1  1  0.181  0.181  0.491  1.0
  Mg  Mg2  1  0.331  0.331  0.005  1.0
  Zn  Zn3  1  0.810  0.810  0.521  1.0
  Zn  Zn4  1  0.010  0.010  0.996  1.0
  Zn  Zn5  1  0.499  0.499  0.499  1.0
  As  As6  1  0.386  0.386  0.304  1.0
  As  As7  1  0.889  0.889  0.762  1.0
  As  As8  1  0.604  0.604  0.727  1.0
  As  As9  1  0.116  0.116  0.214  1.0
[/CIF]
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