The crystal structure described by Ho2SiSeO4 crystallizes in the orthorhombic Pbcm space group. There are two inequivalent Ho sites. In the first Ho site, Ho(1) is bonded in a 6-coordinate geometry to two equivalent Se(1), two equivalent O(2), and four equivalent O(1) atoms. In the second Ho site, Ho(2) is bonded in a 8-coordinate geometry to two equivalent Se(1), two equivalent O(1), and four equivalent O(2) atoms. Si(1) is bonded in a tetrahedral geometry to two equivalent O(1) and two equivalent O(2) atoms. Se(1) is bonded in a 4-coordinate geometry to two equivalent Ho(1) and two equivalent Ho(2) atoms. There are two inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Ho(2), two equivalent Ho(1), and one Si(1) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Ho(1), two equivalent Ho(2), and one Si(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ho2SiSeO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.042
_cell_length_b   6.951
_cell_length_c   10.821
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   454.474
_cell_formula_units_Z   4
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  0.609  0.250  0.500  1.0
  Ho  Ho1  1  0.609  0.250  0.000  1.0
  Ho  Ho2  1  0.391  0.750  0.500  1.0
  Ho  Ho3  1  0.391  0.750  0.000  1.0
  Ho  Ho4  1  0.866  0.528  0.750  1.0
  Ho  Ho5  1  0.866  0.972  0.250  1.0
  Ho  Ho6  1  0.134  0.028  0.750  1.0
  Ho  Ho7  1  0.134  0.472  0.250  1.0
  Si  Si8  1  0.115  0.250  0.500  1.0
  Si  Si9  1  0.885  0.750  0.500  1.0
  Si  Si10  1  0.885  0.750  0.000  1.0
  Si  Si11  1  0.115  0.250  0.000  1.0
  Se  Se12  1  0.571  0.868  0.750  1.0
  Se  Se13  1  0.571  0.632  0.250  1.0
  Se  Se14  1  0.429  0.368  0.750  1.0
  Se  Se15  1  0.429  0.132  0.250  1.0
  O  O16  1  0.278  0.432  0.031  1.0
  O  O17  1  0.278  0.068  0.969  1.0
  O  O18  1  0.722  0.932  0.469  1.0
  O  O19  1  0.722  0.568  0.531  1.0
  O  O20  1  0.722  0.568  0.969  1.0
  O  O21  1  0.722  0.932  0.031  1.0
  O  O22  1  0.278  0.068  0.531  1.0
  O  O23  1  0.278  0.432  0.469  1.0
  O  O24  1  0.052  0.741  0.121  1.0
  O  O25  1  0.052  0.741  0.379  1.0
  O  O26  1  0.948  0.241  0.379  1.0
  O  O27  1  0.948  0.259  0.621  1.0
  O  O28  1  0.948  0.259  0.879  1.0
  O  O29  1  0.948  0.241  0.121  1.0
  O  O30  1  0.052  0.759  0.621  1.0
  O  O31  1  0.052  0.759  0.879  1.0
[/CIF]
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The crystal structure described by Ho2SiSeO4 crystallizes in the orthorhombic Pbcm space group. There are two inequivalent Ho sites. In the first Ho site, Ho(1) is bonded in a 6-coordinate geometry to two equivalent Se(1), two equivalent O(2), and four equivalent O(1) atoms. In the second Ho site, Ho(2) is bonded in a 8-coordinate geometry to two equivalent Se(1), two equivalent O(1), and four equivalent O(2) atoms. Si(1) is bonded in a tetrahedral geometry to two equivalent O(1) and two equivalent O(2) atoms. Se(1) is bonded in a 4-coordinate geometry to two equivalent Ho(1) and two equivalent Ho(2) atoms. There are two inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Ho(2), two equivalent Ho(1), and one Si(1) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Ho(1), two equivalent Ho(2), and one Si(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ho2SiSeO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.042
_cell_length_b   6.951
_cell_length_c   10.821
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   454.474
_cell_formula_units_Z   4
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  0.609  0.250  0.500  1.0
  Ho  Ho1  1  0.609  0.250  0.000  1.0
  Ho  Ho2  1  0.391  0.750  0.500  1.0
  Ho  Ho3  1  0.391  0.750  0.000  1.0
  Ho  Ho4  1  0.866  0.528  0.750  1.0
  Ho  Ho5  1  0.866  0.972  0.250  1.0
  Ho  Ho6  1  0.134  0.028  0.750  1.0
  Ho  Ho7  1  0.134  0.472  0.250  1.0
  Si  Si8  1  0.115  0.250  0.500  1.0
  Si  Si9  1  0.885  0.750  0.500  1.0
  Si  Si10  1  0.885  0.750  0.000  1.0
  Si  Si11  1  0.115  0.250  0.000  1.0
  Se  Se12  1  0.571  0.868  0.750  1.0
  Se  Se13  1  0.571  0.632  0.250  1.0
  Se  Se14  1  0.429  0.368  0.750  1.0
  Se  Se15  1  0.429  0.132  0.250  1.0
  O  O16  1  0.278  0.432  0.031  1.0
  O  O17  1  0.278  0.068  0.969  1.0
  O  O18  1  0.722  0.932  0.469  1.0
  O  O19  1  0.722  0.568  0.531  1.0
  O  O20  1  0.722  0.568  0.969  1.0
  O  O21  1  0.722  0.932  0.031  1.0
  O  O22  1  0.278  0.068  0.531  1.0
  O  O23  1  0.278  0.432  0.469  1.0
  O  O24  1  0.052  0.741  0.121  1.0
  O  O25  1  0.052  0.741  0.379  1.0
  O  O26  1  0.948  0.241  0.379  1.0
  O  O27  1  0.948  0.259  0.621  1.0
  O  O28  1  0.948  0.259  0.879  1.0
  O  O29  1  0.948  0.241  0.121  1.0
  O  O30  1  0.052  0.759  0.621  1.0
  O  O31  1  0.052  0.759  0.879  1.0
[/CIF]
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