The crystal structure described by Cr3Zn2GaSe8 is Spinel-derived structured and crystallizes in the trigonal R-3m space group. Cr(1) is bonded to two equivalent Se(1) and four equivalent Se(2) atoms to form CrSe6 octahedra that share corners with six equivalent Zn(1)Se4 tetrahedra, edges with two equivalent Ga(1)Se6 octahedra, and edges with four equivalent Cr(1)Se6 octahedra. Zn(1) is bonded to one Se(1) and three equivalent Se(2) atoms to form ZnSe4 tetrahedra that share corners with three equivalent Ga(1)Se6 octahedra and corners with nine equivalent Cr(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 57-59°. Ga(1) is bonded to six equivalent Se(2) atoms to form GaSe6 octahedra that share corners with six equivalent Zn(1)Se4 tetrahedra and edges with six equivalent Cr(1)Se6 octahedra. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to three equivalent Cr(1) and one Zn(1) atom to form distorted SeZnCr3 trigonal pyramids that share corners with three equivalent Se(1)ZnCr3 trigonal pyramids, corners with nine equivalent Se(2)ZnCr2Ga trigonal pyramids, and edges with three equivalent Se(2)ZnCr2Ga trigonal pyramids. In the second Se site, Se(2) is bonded to two equivalent Cr(1), one Zn(1), and one Ga(1) atom to form distorted SeZnCr2Ga trigonal pyramids that share corners with three equivalent Se(1)ZnCr3 trigonal pyramids, corners with nine equivalent Se(2)ZnCr2Ga trigonal pyramids,  an edgeedge with one Se(1)ZnCr3 trigonal pyramid, and edges with two equivalent Se(2)ZnCr2Ga trigonal pyramids. is represented by the CIF file [CIF]
data_Zn2Cr3GaSe8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.543
_cell_length_b   7.543
_cell_length_c   7.543
_cell_angle_alpha   59.910
_cell_angle_beta   59.910
_cell_angle_gamma   59.910
_symmetry_Int_Tables_number   1
_cell_volume   302.817
_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
  Zn  Zn0  1  0.124  0.124  0.124  1.0
  Zn  Zn1  1  0.876  0.876  0.876  1.0
  Cr  Cr2  1  0.000  0.500  0.500  1.0
  Cr  Cr3  1  0.500  0.500  0.000  1.0
  Cr  Cr4  1  0.500  0.000  0.500  1.0
  Ga  Ga5  1  0.500  0.500  0.500  1.0
  Se  Se6  1  0.260  0.260  0.260  1.0
  Se  Se7  1  0.720  0.257  0.257  1.0
  Se  Se8  1  0.257  0.257  0.720  1.0
  Se  Se9  1  0.257  0.720  0.257  1.0
  Se  Se10  1  0.740  0.740  0.740  1.0
  Se  Se11  1  0.280  0.743  0.743  1.0
  Se  Se12  1  0.743  0.743  0.280  1.0
  Se  Se13  1  0.743  0.280  0.743  1.0
[/CIF]
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The crystal structure described by Cr3Zn2GaSe8 is Spinel-derived structured and crystallizes in the trigonal R-3m space group. Cr(1) is bonded to two equivalent Se(1) and four equivalent Se(2) atoms to form CrSe6 octahedra that share corners with six equivalent Zn(1)Se4 tetrahedra, edges with two equivalent Ga(1)Se6 octahedra, and edges with four equivalent Cr(1)Se6 octahedra. Zn(1) is bonded to one Se(1) and three equivalent Se(2) atoms to form ZnSe4 tetrahedra that share corners with three equivalent Ga(1)Se6 octahedra and corners with nine equivalent Cr(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 57-59°. Ga(1) is bonded to six equivalent Se(2) atoms to form GaSe6 octahedra that share corners with six equivalent Zn(1)Se4 tetrahedra and edges with six equivalent Cr(1)Se6 octahedra. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to three equivalent Cr(1) and one Zn(1) atom to form distorted SeZnCr3 trigonal pyramids that share corners with three equivalent Se(1)ZnCr3 trigonal pyramids, corners with nine equivalent Se(2)ZnCr2Ga trigonal pyramids, and edges with three equivalent Se(2)ZnCr2Ga trigonal pyramids. In the second Se site, Se(2) is bonded to two equivalent Cr(1), one Zn(1), and one Ga(1) atom to form distorted SeZnCr2Ga trigonal pyramids that share corners with three equivalent Se(1)ZnCr3 trigonal pyramids, corners with nine equivalent Se(2)ZnCr2Ga trigonal pyramids,  an edgeedge with one Se(1)ZnCr3 trigonal pyramid, and edges with two equivalent Se(2)ZnCr2Ga trigonal pyramids. is represented by the CIF file [CIF]
data_Zn2Cr3GaSe8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.543
_cell_length_b   7.543
_cell_length_c   7.543
_cell_angle_alpha   59.910
_cell_angle_beta   59.910
_cell_angle_gamma   59.910
_symmetry_Int_Tables_number   1
_cell_volume   302.817
_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
  Zn  Zn0  1  0.124  0.124  0.124  1.0
  Zn  Zn1  1  0.876  0.876  0.876  1.0
  Cr  Cr2  1  0.000  0.500  0.500  1.0
  Cr  Cr3  1  0.500  0.500  0.000  1.0
  Cr  Cr4  1  0.500  0.000  0.500  1.0
  Ga  Ga5  1  0.500  0.500  0.500  1.0
  Se  Se6  1  0.260  0.260  0.260  1.0
  Se  Se7  1  0.720  0.257  0.257  1.0
  Se  Se8  1  0.257  0.257  0.720  1.0
  Se  Se9  1  0.257  0.720  0.257  1.0
  Se  Se10  1  0.740  0.740  0.740  1.0
  Se  Se11  1  0.280  0.743  0.743  1.0
  Se  Se12  1  0.743  0.743  0.280  1.0
  Se  Se13  1  0.743  0.280  0.743  1.0
[/CIF]
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