The compound described by Mo9Se11 crystallizes in the orthorhombic Cmcm space group. There are four inequivalent Mo sites. In the first Mo site, Mo(1) is bonded to one Se(1), one Se(3), one Se(4), and two equivalent Se(2) atoms to form a mixture of distorted edge and corner-sharing MoSe5 square pyramids. In the second Mo site, Mo(2) is bonded to one Se(1), one Se(3), one Se(5), and two equivalent Se(2) atoms to form a mixture of distorted edge and corner-sharing MoSe5 square pyramids. In the third Mo site, Mo(3) is bonded in a distorted see-saw-like geometry to two equivalent Se(3) and two equivalent Se(4) atoms. In the fourth Mo site, Mo(4) is bonded in a distorted see-saw-like geometry to one Se(4), one Se(5), and two equivalent Se(2) atoms. There are five inequivalent Se sites. In the first Se site, Se(1) is bonded in a 3-coordinate geometry to one Mo(2) and two equivalent Mo(1) atoms. In the second Se site, Se(2) is bonded in a 4-coordinate geometry to one Mo(2), one Mo(4), and two equivalent Mo(1) atoms. In the third Se site, Se(3) is bonded in a 4-coordinate geometry to one Mo(2), one Mo(3), and two equivalent Mo(1) atoms. In the fourth Se site, Se(4) is bonded in a 4-coordinate geometry to one Mo(3), one Mo(4), and two equivalent Mo(1) atoms. In the fifth Se site, Se(5) is bonded in a 4-coordinate geometry to two equivalent Mo(2) and two equivalent Mo(4) atoms. is represented by the CIF file [CIF]
data_Mo9Se11
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.024
_cell_length_b   9.024
_cell_length_c   11.179
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   95.791
_symmetry_Int_Tables_number   1
_cell_volume   905.693
_cell_formula_units_Z   2
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
  Mo  Mo0  1  0.482  0.901  0.370  1.0
  Mo  Mo1  1  0.518  0.099  0.870  1.0
  Mo  Mo2  1  0.901  0.482  0.630  1.0
  Mo  Mo3  1  0.099  0.518  0.130  1.0
  Mo  Mo4  1  0.518  0.099  0.630  1.0
  Mo  Mo5  1  0.482  0.901  0.130  1.0
  Mo  Mo6  1  0.099  0.518  0.370  1.0
  Mo  Mo7  1  0.901  0.482  0.870  1.0
  Mo  Mo8  1  0.693  0.927  0.750  1.0
  Mo  Mo9  1  0.307  0.073  0.250  1.0
  Mo  Mo10  1  0.927  0.693  0.250  1.0
  Mo  Mo11  1  0.073  0.307  0.750  1.0
  Mo  Mo12  1  0.353  0.647  0.250  1.0
  Mo  Mo13  1  0.647  0.353  0.750  1.0
  Mo  Mo14  1  0.822  0.178  0.628  1.0
  Mo  Mo15  1  0.178  0.822  0.128  1.0
  Mo  Mo16  1  0.178  0.822  0.372  1.0
  Mo  Mo17  1  0.822  0.178  0.872  1.0
  Se  Se18  1  0.414  0.872  0.750  1.0
  Se  Se19  1  0.586  0.128  0.250  1.0
  Se  Se20  1  0.872  0.414  0.250  1.0
  Se  Se21  1  0.128  0.586  0.750  1.0
  Se  Se22  1  0.944  0.708  0.482  1.0
  Se  Se23  1  0.056  0.292  0.982  1.0
  Se  Se24  1  0.708  0.944  0.518  1.0
  Se  Se25  1  0.292  0.056  0.018  1.0
  Se  Se26  1  0.056  0.292  0.518  1.0
  Se  Se27  1  0.944  0.708  0.018  1.0
  Se  Se28  1  0.292  0.056  0.482  1.0
  Se  Se29  1  0.708  0.944  0.982  1.0
  Se  Se30  1  0.366  0.279  0.750  1.0
  Se  Se31  1  0.634  0.721  0.250  1.0
  Se  Se32  1  0.279  0.366  0.250  1.0
  Se  Se33  1  0.721  0.634  0.750  1.0
  Se  Se34  1  0.654  0.346  0.518  1.0
  Se  Se35  1  0.346  0.654  0.018  1.0
  Se  Se36  1  0.988  0.012  0.750  1.0
  Se  Se37  1  0.012  0.988  0.250  1.0
  Se  Se38  1  0.654  0.346  0.982  1.0
  Se  Se39  1  0.346  0.654  0.482  1.0
[/CIF]
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The compound described by Mo9Se11 crystallizes in the orthorhombic Cmcm space group. There are four inequivalent Mo sites. In the first Mo site, Mo(1) is bonded to one Se(1), one Se(3), one Se(4), and two equivalent Se(2) atoms to form a mixture of distorted edge and corner-sharing MoSe5 square pyramids. In the second Mo site, Mo(2) is bonded to one Se(1), one Se(3), one Se(5), and two equivalent Se(2) atoms to form a mixture of distorted edge and corner-sharing MoSe5 square pyramids. In the third Mo site, Mo(3) is bonded in a distorted see-saw-like geometry to two equivalent Se(3) and two equivalent Se(4) atoms. In the fourth Mo site, Mo(4) is bonded in a distorted see-saw-like geometry to one Se(4), one Se(5), and two equivalent Se(2) atoms. There are five inequivalent Se sites. In the first Se site, Se(1) is bonded in a 3-coordinate geometry to one Mo(2) and two equivalent Mo(1) atoms. In the second Se site, Se(2) is bonded in a 4-coordinate geometry to one Mo(2), one Mo(4), and two equivalent Mo(1) atoms. In the third Se site, Se(3) is bonded in a 4-coordinate geometry to one Mo(2), one Mo(3), and two equivalent Mo(1) atoms. In the fourth Se site, Se(4) is bonded in a 4-coordinate geometry to one Mo(3), one Mo(4), and two equivalent Mo(1) atoms. In the fifth Se site, Se(5) is bonded in a 4-coordinate geometry to two equivalent Mo(2) and two equivalent Mo(4) atoms. is represented by the CIF file [CIF]
data_Mo9Se11
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.024
_cell_length_b   9.024
_cell_length_c   11.179
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   95.791
_symmetry_Int_Tables_number   1
_cell_volume   905.693
_cell_formula_units_Z   2
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
  Mo  Mo0  1  0.482  0.901  0.370  1.0
  Mo  Mo1  1  0.518  0.099  0.870  1.0
  Mo  Mo2  1  0.901  0.482  0.630  1.0
  Mo  Mo3  1  0.099  0.518  0.130  1.0
  Mo  Mo4  1  0.518  0.099  0.630  1.0
  Mo  Mo5  1  0.482  0.901  0.130  1.0
  Mo  Mo6  1  0.099  0.518  0.370  1.0
  Mo  Mo7  1  0.901  0.482  0.870  1.0
  Mo  Mo8  1  0.693  0.927  0.750  1.0
  Mo  Mo9  1  0.307  0.073  0.250  1.0
  Mo  Mo10  1  0.927  0.693  0.250  1.0
  Mo  Mo11  1  0.073  0.307  0.750  1.0
  Mo  Mo12  1  0.353  0.647  0.250  1.0
  Mo  Mo13  1  0.647  0.353  0.750  1.0
  Mo  Mo14  1  0.822  0.178  0.628  1.0
  Mo  Mo15  1  0.178  0.822  0.128  1.0
  Mo  Mo16  1  0.178  0.822  0.372  1.0
  Mo  Mo17  1  0.822  0.178  0.872  1.0
  Se  Se18  1  0.414  0.872  0.750  1.0
  Se  Se19  1  0.586  0.128  0.250  1.0
  Se  Se20  1  0.872  0.414  0.250  1.0
  Se  Se21  1  0.128  0.586  0.750  1.0
  Se  Se22  1  0.944  0.708  0.482  1.0
  Se  Se23  1  0.056  0.292  0.982  1.0
  Se  Se24  1  0.708  0.944  0.518  1.0
  Se  Se25  1  0.292  0.056  0.018  1.0
  Se  Se26  1  0.056  0.292  0.518  1.0
  Se  Se27  1  0.944  0.708  0.018  1.0
  Se  Se28  1  0.292  0.056  0.482  1.0
  Se  Se29  1  0.708  0.944  0.982  1.0
  Se  Se30  1  0.366  0.279  0.750  1.0
  Se  Se31  1  0.634  0.721  0.250  1.0
  Se  Se32  1  0.279  0.366  0.250  1.0
  Se  Se33  1  0.721  0.634  0.750  1.0
  Se  Se34  1  0.654  0.346  0.518  1.0
  Se  Se35  1  0.346  0.654  0.018  1.0
  Se  Se36  1  0.988  0.012  0.750  1.0
  Se  Se37  1  0.012  0.988  0.250  1.0
  Se  Se38  1  0.654  0.346  0.982  1.0
  Se  Se39  1  0.346  0.654  0.482  1.0
[/CIF]
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