The compound described by SrNb5Se8 crystallizes in the monoclinic C2/m space group. Sr(1) is bonded in a 10-coordinate geometry to two equivalent Se(1), four equivalent Se(2), and four equivalent Se(3) atoms. There are three inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to two equivalent Se(2) and four equivalent Se(1) atoms to form a mixture of distorted edge and corner-sharing NbSe6 octahedra. The corner-sharing octahedral tilt angles are 48°. In the second Nb site, Nb(2) is bonded to one Se(1), two equivalent Se(2), and three equivalent Se(4) atoms to form a mixture of distorted edge, corner, and face-sharing NbSe6 octahedra. The corner-sharing octahedral tilt angles range from 50-53°. In the third Nb site, Nb(3) is bonded to one Se(1), two equivalent Se(4), and three equivalent Se(3) atoms to form a mixture of distorted edge, corner, and face-sharing NbSe6 octahedra. The corner-sharing octahedral tilt angles range from 48-53°. There are four inequivalent Se sites. In the first Se site, Se(1) is bonded in a 5-coordinate geometry to one Sr(1), one Nb(2), one Nb(3), and two equivalent Nb(1) atoms. In the second Se site, Se(2) is bonded in a 5-coordinate geometry to two equivalent Sr(1), one Nb(1), and two equivalent Nb(2) atoms. In the third Se site, Se(3) is bonded in a 5-coordinate geometry to two equivalent Sr(1) and three equivalent Nb(3) atoms. In the fourth Se site, Se(4) is bonded to two equivalent Nb(3) and three equivalent Nb(2) atoms to form distorted edge-sharing SeNb5 trigonal bipyramids. is represented by the CIF file [CIF]
data_SrNb5Se8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.551
_cell_length_b   9.381
_cell_length_c   9.398
_cell_angle_alpha   104.163
_cell_angle_beta   90.000
_cell_angle_gamma   100.910
_symmetry_Int_Tables_number   1
_cell_volume   297.696
_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
  Sr  Sr0  1  0.500  0.000  0.500  1.0
  Nb  Nb1  1  0.000  0.000  0.000  1.0
  Nb  Nb2  1  0.360  0.719  0.012  1.0
  Nb  Nb3  1  0.640  0.281  0.988  1.0
  Nb  Nb4  1  0.288  0.576  0.626  1.0
  Nb  Nb5  1  0.712  0.424  0.374  1.0
  Se  Se6  1  0.573  0.147  0.193  1.0
  Se  Se7  1  0.427  0.853  0.807  1.0
  Se  Se8  1  0.079  0.158  0.796  1.0
  Se  Se9  1  0.921  0.842  0.204  1.0
  Se  Se10  1  0.146  0.292  0.502  1.0
  Se  Se11  1  0.854  0.708  0.498  1.0
  Se  Se12  1  0.240  0.481  0.159  1.0
  Se  Se13  1  0.760  0.519  0.841  1.0
[/CIF]
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The compound described by SrNb5Se8 crystallizes in the monoclinic C2/m space group. Sr(1) is bonded in a 10-coordinate geometry to two equivalent Se(1), four equivalent Se(2), and four equivalent Se(3) atoms. There are three inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to two equivalent Se(2) and four equivalent Se(1) atoms to form a mixture of distorted edge and corner-sharing NbSe6 octahedra. The corner-sharing octahedral tilt angles are 48°. In the second Nb site, Nb(2) is bonded to one Se(1), two equivalent Se(2), and three equivalent Se(4) atoms to form a mixture of distorted edge, corner, and face-sharing NbSe6 octahedra. The corner-sharing octahedral tilt angles range from 50-53°. In the third Nb site, Nb(3) is bonded to one Se(1), two equivalent Se(4), and three equivalent Se(3) atoms to form a mixture of distorted edge, corner, and face-sharing NbSe6 octahedra. The corner-sharing octahedral tilt angles range from 48-53°. There are four inequivalent Se sites. In the first Se site, Se(1) is bonded in a 5-coordinate geometry to one Sr(1), one Nb(2), one Nb(3), and two equivalent Nb(1) atoms. In the second Se site, Se(2) is bonded in a 5-coordinate geometry to two equivalent Sr(1), one Nb(1), and two equivalent Nb(2) atoms. In the third Se site, Se(3) is bonded in a 5-coordinate geometry to two equivalent Sr(1) and three equivalent Nb(3) atoms. In the fourth Se site, Se(4) is bonded to two equivalent Nb(3) and three equivalent Nb(2) atoms to form distorted edge-sharing SeNb5 trigonal bipyramids. is represented by the CIF file [CIF]
data_SrNb5Se8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.551
_cell_length_b   9.381
_cell_length_c   9.398
_cell_angle_alpha   104.163
_cell_angle_beta   90.000
_cell_angle_gamma   100.910
_symmetry_Int_Tables_number   1
_cell_volume   297.696
_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
  Sr  Sr0  1  0.500  0.000  0.500  1.0
  Nb  Nb1  1  0.000  0.000  0.000  1.0
  Nb  Nb2  1  0.360  0.719  0.012  1.0
  Nb  Nb3  1  0.640  0.281  0.988  1.0
  Nb  Nb4  1  0.288  0.576  0.626  1.0
  Nb  Nb5  1  0.712  0.424  0.374  1.0
  Se  Se6  1  0.573  0.147  0.193  1.0
  Se  Se7  1  0.427  0.853  0.807  1.0
  Se  Se8  1  0.079  0.158  0.796  1.0
  Se  Se9  1  0.921  0.842  0.204  1.0
  Se  Se10  1  0.146  0.292  0.502  1.0
  Se  Se11  1  0.854  0.708  0.498  1.0
  Se  Se12  1  0.240  0.481  0.159  1.0
  Se  Se13  1  0.760  0.519  0.841  1.0
[/CIF]
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