The compound described by In2Se crystallizes in the orthorhombic Pnnm space group. There are four inequivalent In sites. In the first In site, In(1) is bonded in a distorted L-shaped geometry to two equivalent Se(1) atoms. In the second In site, In(2) is bonded in a 3-coordinate geometry to one Se(2) and two equivalent Se(1) atoms. In the third In site, In(3) is bonded in a 3-coordinate geometry to one Se(1) and two equivalent Se(2) atoms. In the fourth In site, In(4) is bonded in a distorted T-shaped geometry to one Se(1) and two equivalent Se(2) atoms. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to one In(3), one In(4), two equivalent In(1), and two equivalent In(2) atoms to form SeIn6 octahedra that share corners with two equivalent Se(2)In5 trigonal bipyramids, edges with two equivalent Se(1)In6 octahedra, and edges with two equivalent Se(2)In5 trigonal bipyramids. In the second Se site, Se(2) is bonded to one In(2), two equivalent In(3), and two equivalent In(4) atoms to form SeIn5 trigonal bipyramids that share corners with two equivalent Se(1)In6 octahedra, corners with two equivalent Se(2)In5 trigonal bipyramids, edges with two equivalent Se(1)In6 octahedra, and  an edgeedge with one Se(2)In5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 14-74°. is represented by the CIF card [CIF]
data_In2Se
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.093
_cell_length_b   11.612
_cell_length_c   15.162
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   720.579
_cell_formula_units_Z   8
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
  In  In0  1  0.500  0.094  0.860  1.0
  In  In1  1  0.000  0.594  0.640  1.0
  In  In2  1  0.500  0.253  0.239  1.0
  In  In3  1  0.500  0.747  0.761  1.0
  In  In4  1  0.500  0.692  0.492  1.0
  In  In5  1  0.500  0.587  0.122  1.0
  In  In6  1  0.000  0.753  0.261  1.0
  In  In7  1  0.500  0.308  0.508  1.0
  In  In8  1  0.000  0.087  0.378  1.0
  In  In9  1  0.500  0.413  0.878  1.0
  In  In10  1  0.000  0.913  0.622  1.0
  In  In11  1  0.000  0.247  0.739  1.0
  In  In12  1  0.000  0.808  0.992  1.0
  In  In13  1  0.000  0.192  0.008  1.0
  In  In14  1  0.000  0.406  0.360  1.0
  In  In15  1  0.500  0.906  0.140  1.0
  Se  Se16  1  0.000  0.085  0.176  1.0
  Se  Se17  1  0.500  0.585  0.324  1.0
  Se  Se18  1  0.500  0.347  0.069  1.0
  Se  Se19  1  0.000  0.915  0.824  1.0
  Se  Se20  1  0.500  0.415  0.676  1.0
  Se  Se21  1  0.000  0.153  0.569  1.0
  Se  Se22  1  0.500  0.653  0.931  1.0
  Se  Se23  1  0.000  0.847  0.431  1.0
[/CIF]
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The compound described by In2Se crystallizes in the orthorhombic Pnnm space group. There are four inequivalent In sites. In the first In site, In(1) is bonded in a distorted L-shaped geometry to two equivalent Se(1) atoms. In the second In site, In(2) is bonded in a 3-coordinate geometry to one Se(2) and two equivalent Se(1) atoms. In the third In site, In(3) is bonded in a 3-coordinate geometry to one Se(1) and two equivalent Se(2) atoms. In the fourth In site, In(4) is bonded in a distorted T-shaped geometry to one Se(1) and two equivalent Se(2) atoms. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to one In(3), one In(4), two equivalent In(1), and two equivalent In(2) atoms to form SeIn6 octahedra that share corners with two equivalent Se(2)In5 trigonal bipyramids, edges with two equivalent Se(1)In6 octahedra, and edges with two equivalent Se(2)In5 trigonal bipyramids. In the second Se site, Se(2) is bonded to one In(2), two equivalent In(3), and two equivalent In(4) atoms to form SeIn5 trigonal bipyramids that share corners with two equivalent Se(1)In6 octahedra, corners with two equivalent Se(2)In5 trigonal bipyramids, edges with two equivalent Se(1)In6 octahedra, and  an edgeedge with one Se(2)In5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 14-74°. is represented by the CIF card [CIF]
data_In2Se
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.093
_cell_length_b   11.612
_cell_length_c   15.162
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   720.579
_cell_formula_units_Z   8
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
  In  In0  1  0.500  0.094  0.860  1.0
  In  In1  1  0.000  0.594  0.640  1.0
  In  In2  1  0.500  0.253  0.239  1.0
  In  In3  1  0.500  0.747  0.761  1.0
  In  In4  1  0.500  0.692  0.492  1.0
  In  In5  1  0.500  0.587  0.122  1.0
  In  In6  1  0.000  0.753  0.261  1.0
  In  In7  1  0.500  0.308  0.508  1.0
  In  In8  1  0.000  0.087  0.378  1.0
  In  In9  1  0.500  0.413  0.878  1.0
  In  In10  1  0.000  0.913  0.622  1.0
  In  In11  1  0.000  0.247  0.739  1.0
  In  In12  1  0.000  0.808  0.992  1.0
  In  In13  1  0.000  0.192  0.008  1.0
  In  In14  1  0.000  0.406  0.360  1.0
  In  In15  1  0.500  0.906  0.140  1.0
  Se  Se16  1  0.000  0.085  0.176  1.0
  Se  Se17  1  0.500  0.585  0.324  1.0
  Se  Se18  1  0.500  0.347  0.069  1.0
  Se  Se19  1  0.000  0.915  0.824  1.0
  Se  Se20  1  0.500  0.415  0.676  1.0
  Se  Se21  1  0.000  0.153  0.569  1.0
  Se  Se22  1  0.500  0.653  0.931  1.0
  Se  Se23  1  0.000  0.847  0.431  1.0
[/CIF]
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