The material structure described by In2Se3 crystallizes in the hexagonal P6_1 space group. There are two inequivalent In sites. In the first In site, In(1) is bonded to one Se(2), one Se(3), and two equivalent Se(1) atoms to form InSe4 tetrahedra that share corners with two equivalent In(1)Se4 tetrahedra, corners with four equivalent In(2)Se5 trigonal bipyramids, and  an edgeedge with one In(2)Se5 trigonal bipyramid. In the second In site, In(2) is bonded to one Se(1), two equivalent Se(2), and two equivalent Se(3) atoms to form InSe5 trigonal bipyramids that share corners with four equivalent In(1)Se4 tetrahedra,  an edgeedge with one In(1)Se4 tetrahedra, and edges with two equivalent In(2)Se5 trigonal bipyramids. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded in a trigonal non-coplanar geometry to one In(2) and two equivalent In(1) atoms. In the second Se site, Se(2) is bonded in a trigonal non-coplanar geometry to one In(1) and two equivalent In(2) atoms. In the third Se site, Se(3) is bonded in a distorted trigonal non-coplanar geometry to one In(1) and two equivalent In(2) atoms. is represented by the CIF file [CIF]
data_In2Se3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.274
_cell_length_b   7.274
_cell_length_c   19.543
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   895.379
_cell_formula_units_Z   6
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  0.330  0.987  0.000  1.0
  In  In1  1  0.013  0.343  0.334  1.0
  In  In2  1  0.008  0.697  0.472  1.0
  In  In3  1  0.992  0.303  0.972  1.0
  In  In4  1  0.987  0.657  0.834  1.0
  In  In5  1  0.343  0.330  0.167  1.0
  In  In6  1  0.657  0.670  0.667  1.0
  In  In7  1  0.670  0.013  0.500  1.0
  In  In8  1  0.311  0.008  0.639  1.0
  In  In9  1  0.303  0.311  0.805  1.0
  In  In10  1  0.689  0.992  0.139  1.0
  In  In11  1  0.697  0.689  0.305  1.0
  Se  Se12  1  0.690  0.034  0.635  1.0
  Se  Se13  1  0.638  0.668  0.453  1.0
  Se  Se14  1  0.933  0.278  0.827  1.0
  Se  Se15  1  0.970  0.638  0.620  1.0
  Se  Se16  1  0.344  0.310  0.302  1.0
  Se  Se17  1  0.067  0.722  0.327  1.0
  Se  Se18  1  0.966  0.656  0.969  1.0
  Se  Se19  1  0.668  0.030  0.287  1.0
  Se  Se20  1  0.310  0.966  0.135  1.0
  Se  Se21  1  0.278  0.345  0.660  1.0
  Se  Se22  1  0.655  0.933  0.993  1.0
  Se  Se23  1  0.345  0.067  0.493  1.0
  Se  Se24  1  0.656  0.690  0.802  1.0
  Se  Se25  1  0.332  0.970  0.787  1.0
  Se  Se26  1  0.722  0.655  0.160  1.0
  Se  Se27  1  0.362  0.332  0.953  1.0
  Se  Se28  1  0.030  0.362  0.120  1.0
  Se  Se29  1  0.034  0.344  0.469  1.0
[/CIF]
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The material structure described by In2Se3 crystallizes in the hexagonal P6_1 space group. There are two inequivalent In sites. In the first In site, In(1) is bonded to one Se(2), one Se(3), and two equivalent Se(1) atoms to form InSe4 tetrahedra that share corners with two equivalent In(1)Se4 tetrahedra, corners with four equivalent In(2)Se5 trigonal bipyramids, and  an edgeedge with one In(2)Se5 trigonal bipyramid. In the second In site, In(2) is bonded to one Se(1), two equivalent Se(2), and two equivalent Se(3) atoms to form InSe5 trigonal bipyramids that share corners with four equivalent In(1)Se4 tetrahedra,  an edgeedge with one In(1)Se4 tetrahedra, and edges with two equivalent In(2)Se5 trigonal bipyramids. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded in a trigonal non-coplanar geometry to one In(2) and two equivalent In(1) atoms. In the second Se site, Se(2) is bonded in a trigonal non-coplanar geometry to one In(1) and two equivalent In(2) atoms. In the third Se site, Se(3) is bonded in a distorted trigonal non-coplanar geometry to one In(1) and two equivalent In(2) atoms. is represented by the CIF file [CIF]
data_In2Se3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.274
_cell_length_b   7.274
_cell_length_c   19.543
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   895.379
_cell_formula_units_Z   6
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  0.330  0.987  0.000  1.0
  In  In1  1  0.013  0.343  0.334  1.0
  In  In2  1  0.008  0.697  0.472  1.0
  In  In3  1  0.992  0.303  0.972  1.0
  In  In4  1  0.987  0.657  0.834  1.0
  In  In5  1  0.343  0.330  0.167  1.0
  In  In6  1  0.657  0.670  0.667  1.0
  In  In7  1  0.670  0.013  0.500  1.0
  In  In8  1  0.311  0.008  0.639  1.0
  In  In9  1  0.303  0.311  0.805  1.0
  In  In10  1  0.689  0.992  0.139  1.0
  In  In11  1  0.697  0.689  0.305  1.0
  Se  Se12  1  0.690  0.034  0.635  1.0
  Se  Se13  1  0.638  0.668  0.453  1.0
  Se  Se14  1  0.933  0.278  0.827  1.0
  Se  Se15  1  0.970  0.638  0.620  1.0
  Se  Se16  1  0.344  0.310  0.302  1.0
  Se  Se17  1  0.067  0.722  0.327  1.0
  Se  Se18  1  0.966  0.656  0.969  1.0
  Se  Se19  1  0.668  0.030  0.287  1.0
  Se  Se20  1  0.310  0.966  0.135  1.0
  Se  Se21  1  0.278  0.345  0.660  1.0
  Se  Se22  1  0.655  0.933  0.993  1.0
  Se  Se23  1  0.345  0.067  0.493  1.0
  Se  Se24  1  0.656  0.690  0.802  1.0
  Se  Se25  1  0.332  0.970  0.787  1.0
  Se  Se26  1  0.722  0.655  0.160  1.0
  Se  Se27  1  0.362  0.332  0.953  1.0
  Se  Se28  1  0.030  0.362  0.120  1.0
  Se  Se29  1  0.034  0.344  0.469  1.0
[/CIF]
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