The material described by Rb2Mo9Se10 crystallizes in the trigonal R-3 space group. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a 10-coordinate geometry to one Se(1), three equivalent Se(3), and six equivalent Se(4) atoms. In the second Rb site, Rb(2) is bonded in a 9-coordinate geometry to three equivalent Se(2), three equivalent Se(3), and three equivalent Se(4) atoms. There are three inequivalent Mo sites. In the first Mo site, Mo(1) is bonded to one Se(1), one Se(3), and three 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 in a distorted see-saw-like geometry to one Se(2), one Se(4), and two equivalent Se(3) atoms. In the third Mo site, Mo(3) is bonded in a distorted see-saw-like geometry to one Se(3) and three equivalent Se(4) atoms. There are four inequivalent Se sites. In the first Se site, Se(1) is bonded in a 4-coordinate geometry to one Rb(1) and three equivalent Mo(1) atoms. In the second Se site, Se(2) is bonded in a distorted pentagonal planar geometry to one Rb(2), one Mo(2), and three equivalent Mo(1) atoms. In the third Se site, Se(3) is bonded in a 6-coordinate geometry to one Rb(1), one Rb(2), one Mo(1), one Mo(3), and two equivalent Mo(2) atoms. In the fourth Se site, Se(4) is bonded in a 7-coordinate geometry to one Rb(2), two equivalent Rb(1), one Mo(2), and three equivalent Mo(3) atoms. is represented by the CIF card [CIF]
data_Rb2Mo9Se10
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   14.051
_cell_length_b   14.051
_cell_length_c   14.051
_cell_angle_alpha   40.509
_cell_angle_beta   40.509
_cell_angle_gamma   40.509
_symmetry_Int_Tables_number   1
_cell_volume   1055.697
_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
  Rb  Rb0  1  0.295  0.295  0.295  1.0
  Rb  Rb1  1  0.705  0.705  0.705  1.0
  Rb  Rb2  1  0.424  0.424  0.424  1.0
  Rb  Rb3  1  0.576  0.576  0.576  1.0
  Mo  Mo4  1  0.314  0.001  0.126  1.0
  Mo  Mo5  1  0.001  0.126  0.314  1.0
  Mo  Mo6  1  0.126  0.314  0.001  1.0
  Mo  Mo7  1  0.686  0.999  0.874  1.0
  Mo  Mo8  1  0.999  0.874  0.686  1.0
  Mo  Mo9  1  0.874  0.686  0.999  1.0
  Mo  Mo10  1  0.921  0.238  0.104  1.0
  Mo  Mo11  1  0.238  0.104  0.921  1.0
  Mo  Mo12  1  0.104  0.921  0.238  1.0
  Mo  Mo13  1  0.079  0.762  0.896  1.0
  Mo  Mo14  1  0.762  0.896  0.079  1.0
  Mo  Mo15  1  0.896  0.079  0.762  1.0
  Mo  Mo16  1  0.804  0.118  0.989  1.0
  Mo  Mo17  1  0.118  0.989  0.804  1.0
  Mo  Mo18  1  0.989  0.804  0.118  1.0
  Mo  Mo19  1  0.196  0.882  0.011  1.0
  Mo  Mo20  1  0.882  0.011  0.196  1.0
  Mo  Mo21  1  0.011  0.196  0.882  1.0
  Se  Se22  1  0.200  0.200  0.200  1.0
  Se  Se23  1  0.800  0.800  0.800  1.0
  Se  Se24  1  0.813  0.433  0.182  1.0
  Se  Se25  1  0.433  0.182  0.813  1.0
  Se  Se26  1  0.182  0.813  0.433  1.0
  Se  Se27  1  0.187  0.567  0.818  1.0
  Se  Se28  1  0.567  0.818  0.187  1.0
  Se  Se29  1  0.818  0.187  0.567  1.0
  Se  Se30  1  0.585  0.203  0.946  1.0
  Se  Se31  1  0.203  0.946  0.585  1.0
  Se  Se32  1  0.946  0.585  0.203  1.0
  Se  Se33  1  0.415  0.797  0.054  1.0
  Se  Se34  1  0.797  0.054  0.415  1.0
  Se  Se35  1  0.054  0.415  0.797  1.0
  Se  Se36  1  0.932  0.303  0.679  1.0
  Se  Se37  1  0.303  0.679  0.932  1.0
  Se  Se38  1  0.679  0.932  0.303  1.0
  Se  Se39  1  0.068  0.697  0.321  1.0
  Se  Se40  1  0.697  0.321  0.068  1.0
  Se  Se41  1  0.321  0.068  0.697  1.0
[/CIF]
.
The material described by Rb2Mo9Se10 crystallizes in the trigonal R-3 space group. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a 10-coordinate geometry to one Se(1), three equivalent Se(3), and six equivalent Se(4) atoms. In the second Rb site, Rb(2) is bonded in a 9-coordinate geometry to three equivalent Se(2), three equivalent Se(3), and three equivalent Se(4) atoms. There are three inequivalent Mo sites. In the first Mo site, Mo(1) is bonded to one Se(1), one Se(3), and three 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 in a distorted see-saw-like geometry to one Se(2), one Se(4), and two equivalent Se(3) atoms. In the third Mo site, Mo(3) is bonded in a distorted see-saw-like geometry to one Se(3) and three equivalent Se(4) atoms. There are four inequivalent Se sites. In the first Se site, Se(1) is bonded in a 4-coordinate geometry to one Rb(1) and three equivalent Mo(1) atoms. In the second Se site, Se(2) is bonded in a distorted pentagonal planar geometry to one Rb(2), one Mo(2), and three equivalent Mo(1) atoms. In the third Se site, Se(3) is bonded in a 6-coordinate geometry to one Rb(1), one Rb(2), one Mo(1), one Mo(3), and two equivalent Mo(2) atoms. In the fourth Se site, Se(4) is bonded in a 7-coordinate geometry to one Rb(2), two equivalent Rb(1), one Mo(2), and three equivalent Mo(3) atoms. is represented by the CIF card [CIF]
data_Rb2Mo9Se10
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   14.051
_cell_length_b   14.051
_cell_length_c   14.051
_cell_angle_alpha   40.509
_cell_angle_beta   40.509
_cell_angle_gamma   40.509
_symmetry_Int_Tables_number   1
_cell_volume   1055.697
_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
  Rb  Rb0  1  0.295  0.295  0.295  1.0
  Rb  Rb1  1  0.705  0.705  0.705  1.0
  Rb  Rb2  1  0.424  0.424  0.424  1.0
  Rb  Rb3  1  0.576  0.576  0.576  1.0
  Mo  Mo4  1  0.314  0.001  0.126  1.0
  Mo  Mo5  1  0.001  0.126  0.314  1.0
  Mo  Mo6  1  0.126  0.314  0.001  1.0
  Mo  Mo7  1  0.686  0.999  0.874  1.0
  Mo  Mo8  1  0.999  0.874  0.686  1.0
  Mo  Mo9  1  0.874  0.686  0.999  1.0
  Mo  Mo10  1  0.921  0.238  0.104  1.0
  Mo  Mo11  1  0.238  0.104  0.921  1.0
  Mo  Mo12  1  0.104  0.921  0.238  1.0
  Mo  Mo13  1  0.079  0.762  0.896  1.0
  Mo  Mo14  1  0.762  0.896  0.079  1.0
  Mo  Mo15  1  0.896  0.079  0.762  1.0
  Mo  Mo16  1  0.804  0.118  0.989  1.0
  Mo  Mo17  1  0.118  0.989  0.804  1.0
  Mo  Mo18  1  0.989  0.804  0.118  1.0
  Mo  Mo19  1  0.196  0.882  0.011  1.0
  Mo  Mo20  1  0.882  0.011  0.196  1.0
  Mo  Mo21  1  0.011  0.196  0.882  1.0
  Se  Se22  1  0.200  0.200  0.200  1.0
  Se  Se23  1  0.800  0.800  0.800  1.0
  Se  Se24  1  0.813  0.433  0.182  1.0
  Se  Se25  1  0.433  0.182  0.813  1.0
  Se  Se26  1  0.182  0.813  0.433  1.0
  Se  Se27  1  0.187  0.567  0.818  1.0
  Se  Se28  1  0.567  0.818  0.187  1.0
  Se  Se29  1  0.818  0.187  0.567  1.0
  Se  Se30  1  0.585  0.203  0.946  1.0
  Se  Se31  1  0.203  0.946  0.585  1.0
  Se  Se32  1  0.946  0.585  0.203  1.0
  Se  Se33  1  0.415  0.797  0.054  1.0
  Se  Se34  1  0.797  0.054  0.415  1.0
  Se  Se35  1  0.054  0.415  0.797  1.0
  Se  Se36  1  0.932  0.303  0.679  1.0
  Se  Se37  1  0.303  0.679  0.932  1.0
  Se  Se38  1  0.679  0.932  0.303  1.0
  Se  Se39  1  0.068  0.697  0.321  1.0
  Se  Se40  1  0.697  0.321  0.068  1.0
  Se  Se41  1  0.321  0.068  0.697  1.0
[/CIF]
.