The material described by Ho2Se3 crystallizes in the tetragonal I-42d space group. There are three inequivalent Ho sites. In the first Ho site, Ho(1) is bonded in a 8-coordinate geometry to two equivalent Se(2), three equivalent Se(1), and three equivalent Se(3) atoms. In the second Ho site, Ho(2) is bonded in a 8-coordinate geometry to two equivalent Se(2), two equivalent Se(3), and four equivalent Se(1) atoms. In the third Ho site, Ho(3) is bonded in a 8-coordinate geometry to two equivalent Se(1), two equivalent Se(3), and four equivalent Se(2) atoms. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded to one Ho(3), two equivalent Ho(2), and three equivalent Ho(1) atoms to form distorted SeHo6 octahedra that share corners with three equivalent Se(1)Ho6 octahedra, corners with five equivalent Se(2)Ho5 square pyramids, corners with seven equivalent Se(3)Ho5 square pyramids, edges with two equivalent Se(1)Ho6 octahedra,  an edgeedge with one Se(3)Ho5 square pyramid, edges with three equivalent Se(2)Ho5 square pyramids, faces with two equivalent Se(1)Ho6 octahedra,  a faceface with one Se(2)Ho5 square pyramid, and faces with two equivalent Se(3)Ho5 square pyramids. The corner-sharing octahedral tilt angles range from 18-50°. In the second Se site, Se(2) is bonded to one Ho(2), two equivalent Ho(1), and two equivalent Ho(3) atoms to form distorted SeHo5 square pyramids that share corners with five equivalent Se(1)Ho6 octahedra, corners with four equivalent Se(2)Ho5 square pyramids, corners with four equivalent Se(3)Ho5 square pyramids, edges with three equivalent Se(1)Ho6 octahedra,  an edgeedge with one Se(2)Ho5 square pyramid, edges with four equivalent Se(3)Ho5 square pyramids,  a faceface with one Se(1)Ho6 octahedra, and  a faceface with one Se(2)Ho5 square pyramid. The corner-sharing octahedral tilt angles range from 24-49°. In the third Se site, Se(3) is bonded to one Ho(2), one Ho(3), and three equivalent Ho(1) atoms to form distorted SeHo5 square pyramids that share corners with seven equivalent Se(1)Ho6 octahedra, corners with four equivalent Se(2)Ho5 square pyramids, corners with five equivalent Se(3)Ho5 square pyramids,  an edgeedge with one Se(1)Ho6 octahedra, edges with four equivalent Se(2)Ho5 square pyramids, faces with two equivalent Se(1)Ho6 octahedra, and  a faceface with one Se(3)Ho5 square pyramid. The corner-sharing octahedral tilt angles range from 15-53°. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ho2Se3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   14.353
_cell_length_b   14.353
_cell_length_c   14.353
_cell_angle_alpha   144.826
_cell_angle_beta   144.826
_cell_angle_gamma   50.593
_symmetry_Int_Tables_number   1
_cell_volume   976.287
_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
  Ho  Ho0  1  0.720  0.595  0.394  1.0
  Ho  Ho1  1  0.201  0.326  0.606  1.0
  Ho  Ho2  1  0.418  0.918  0.500  1.0
  Ho  Ho3  1  0.992  0.625  0.867  1.0
  Ho  Ho4  1  0.332  0.332  0.000  1.0
  Ho  Ho5  1  0.030  0.924  0.375  1.0
  Ho  Ho6  1  0.549  0.655  0.625  1.0
  Ho  Ho7  1  0.758  0.125  0.133  1.0
  Ho  Ho8  1  0.345  0.970  0.894  1.0
  Ho  Ho9  1  0.668  0.668  0.000  1.0
  Ho  Ho10  1  0.375  0.242  0.367  1.0
  Ho  Ho11  1  0.875  0.008  0.633  1.0
  Ho  Ho12  1  0.076  0.451  0.106  1.0
  Ho  Ho13  1  0.082  0.582  0.500  1.0
  Ho  Ho14  1  0.674  0.280  0.875  1.0
  Ho  Ho15  1  0.405  0.799  0.125  1.0
  Se  Se16  1  0.500  0.255  0.886  1.0
  Se  Se17  1  0.711  0.826  0.747  1.0
  Se  Se18  1  0.369  0.615  0.114  1.0
  Se  Se19  1  0.250  0.635  0.255  1.0
  Se  Se20  1  0.381  0.995  0.745  1.0
  Se  Se21  1  0.671  0.424  0.385  1.0
  Se  Se22  1  0.079  0.964  0.253  1.0
  Se  Se23  1  0.847  0.591  0.903  1.0
  Se  Se24  1  0.039  0.286  0.615  1.0
  Se  Se25  1  0.056  0.153  0.744  1.0
  Se  Se26  1  0.689  0.944  0.097  1.0
  Se  Se27  1  0.576  0.961  0.247  1.0
  Se  Se28  1  0.714  0.329  0.753  1.0
  Se  Se29  1  0.005  0.750  0.386  1.0
  Se  Se30  1  0.409  0.311  0.256  1.0
  Se  Se31  1  0.174  0.921  0.885  1.0
  Se  Se32  1  0.365  0.619  0.614  1.0
  Se  Se33  1  0.385  0.500  0.755  1.0
  Se  Se34  1  0.036  0.289  0.115  1.0
  Se  Se35  1  0.903  0.306  0.244  1.0
  Se  Se36  1  0.061  0.659  0.756  1.0
  Se  Se37  1  0.341  0.097  0.403  1.0
  Se  Se38  1  0.745  0.631  0.245  1.0
  Se  Se39  1  0.694  0.939  0.597  1.0
[/CIF]
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The material described by Ho2Se3 crystallizes in the tetragonal I-42d space group. There are three inequivalent Ho sites. In the first Ho site, Ho(1) is bonded in a 8-coordinate geometry to two equivalent Se(2), three equivalent Se(1), and three equivalent Se(3) atoms. In the second Ho site, Ho(2) is bonded in a 8-coordinate geometry to two equivalent Se(2), two equivalent Se(3), and four equivalent Se(1) atoms. In the third Ho site, Ho(3) is bonded in a 8-coordinate geometry to two equivalent Se(1), two equivalent Se(3), and four equivalent Se(2) atoms. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded to one Ho(3), two equivalent Ho(2), and three equivalent Ho(1) atoms to form distorted SeHo6 octahedra that share corners with three equivalent Se(1)Ho6 octahedra, corners with five equivalent Se(2)Ho5 square pyramids, corners with seven equivalent Se(3)Ho5 square pyramids, edges with two equivalent Se(1)Ho6 octahedra,  an edgeedge with one Se(3)Ho5 square pyramid, edges with three equivalent Se(2)Ho5 square pyramids, faces with two equivalent Se(1)Ho6 octahedra,  a faceface with one Se(2)Ho5 square pyramid, and faces with two equivalent Se(3)Ho5 square pyramids. The corner-sharing octahedral tilt angles range from 18-50°. In the second Se site, Se(2) is bonded to one Ho(2), two equivalent Ho(1), and two equivalent Ho(3) atoms to form distorted SeHo5 square pyramids that share corners with five equivalent Se(1)Ho6 octahedra, corners with four equivalent Se(2)Ho5 square pyramids, corners with four equivalent Se(3)Ho5 square pyramids, edges with three equivalent Se(1)Ho6 octahedra,  an edgeedge with one Se(2)Ho5 square pyramid, edges with four equivalent Se(3)Ho5 square pyramids,  a faceface with one Se(1)Ho6 octahedra, and  a faceface with one Se(2)Ho5 square pyramid. The corner-sharing octahedral tilt angles range from 24-49°. In the third Se site, Se(3) is bonded to one Ho(2), one Ho(3), and three equivalent Ho(1) atoms to form distorted SeHo5 square pyramids that share corners with seven equivalent Se(1)Ho6 octahedra, corners with four equivalent Se(2)Ho5 square pyramids, corners with five equivalent Se(3)Ho5 square pyramids,  an edgeedge with one Se(1)Ho6 octahedra, edges with four equivalent Se(2)Ho5 square pyramids, faces with two equivalent Se(1)Ho6 octahedra, and  a faceface with one Se(3)Ho5 square pyramid. The corner-sharing octahedral tilt angles range from 15-53°. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ho2Se3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   14.353
_cell_length_b   14.353
_cell_length_c   14.353
_cell_angle_alpha   144.826
_cell_angle_beta   144.826
_cell_angle_gamma   50.593
_symmetry_Int_Tables_number   1
_cell_volume   976.287
_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
  Ho  Ho0  1  0.720  0.595  0.394  1.0
  Ho  Ho1  1  0.201  0.326  0.606  1.0
  Ho  Ho2  1  0.418  0.918  0.500  1.0
  Ho  Ho3  1  0.992  0.625  0.867  1.0
  Ho  Ho4  1  0.332  0.332  0.000  1.0
  Ho  Ho5  1  0.030  0.924  0.375  1.0
  Ho  Ho6  1  0.549  0.655  0.625  1.0
  Ho  Ho7  1  0.758  0.125  0.133  1.0
  Ho  Ho8  1  0.345  0.970  0.894  1.0
  Ho  Ho9  1  0.668  0.668  0.000  1.0
  Ho  Ho10  1  0.375  0.242  0.367  1.0
  Ho  Ho11  1  0.875  0.008  0.633  1.0
  Ho  Ho12  1  0.076  0.451  0.106  1.0
  Ho  Ho13  1  0.082  0.582  0.500  1.0
  Ho  Ho14  1  0.674  0.280  0.875  1.0
  Ho  Ho15  1  0.405  0.799  0.125  1.0
  Se  Se16  1  0.500  0.255  0.886  1.0
  Se  Se17  1  0.711  0.826  0.747  1.0
  Se  Se18  1  0.369  0.615  0.114  1.0
  Se  Se19  1  0.250  0.635  0.255  1.0
  Se  Se20  1  0.381  0.995  0.745  1.0
  Se  Se21  1  0.671  0.424  0.385  1.0
  Se  Se22  1  0.079  0.964  0.253  1.0
  Se  Se23  1  0.847  0.591  0.903  1.0
  Se  Se24  1  0.039  0.286  0.615  1.0
  Se  Se25  1  0.056  0.153  0.744  1.0
  Se  Se26  1  0.689  0.944  0.097  1.0
  Se  Se27  1  0.576  0.961  0.247  1.0
  Se  Se28  1  0.714  0.329  0.753  1.0
  Se  Se29  1  0.005  0.750  0.386  1.0
  Se  Se30  1  0.409  0.311  0.256  1.0
  Se  Se31  1  0.174  0.921  0.885  1.0
  Se  Se32  1  0.365  0.619  0.614  1.0
  Se  Se33  1  0.385  0.500  0.755  1.0
  Se  Se34  1  0.036  0.289  0.115  1.0
  Se  Se35  1  0.903  0.306  0.244  1.0
  Se  Se36  1  0.061  0.659  0.756  1.0
  Se  Se37  1  0.341  0.097  0.403  1.0
  Se  Se38  1  0.745  0.631  0.245  1.0
  Se  Se39  1  0.694  0.939  0.597  1.0
[/CIF]
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