data_MgRh2Se
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.24
_cell_length_b   8.24
_cell_length_c   8.24
_cell_angle_alpha   21.23
_cell_angle_beta   21.23
_cell_angle_gamma   21.23
_symmetry_Int_Tables_number   1
_chemical_formula_structural   MgRh2Se
_chemical_formula_sum   'Mg1 Rh2 Se1'
_cell_volume   64.36
_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
  Mg  Mg0  1  0.0  0.0  0.0  1.0
  Rh  Rh1  1  0.0  0.0  0.9  1.0
  Rh  Rh2  1  0.0  0.0  0.27  1.0
  Se  Se3  1  0.0  0.0  0.08  1.0

data_MgRh2Se
_symmetry_space_group_name_H-M   Cm
_cell_length_a   5.26
_cell_length_b   3.04
_cell_length_c   8.24
_cell_angle_alpha   90.0
_cell_angle_beta   102.28
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   MgRh2Se
_chemical_formula_sum   'Mg2 Rh4 Se2'
_cell_volume   128.71
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  'x, -y, z'
  3  'x+1/2, y+1/2, z'
  4  'x+1/2, -y+1/2, 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
  Mg  Mg0  2  0.0  0.0  0.0  1.0
  Rh  Rh1  2  -0.0  0.0  0.73  1.0
  Rh  Rh2  2  -0.0  0.0  0.1  1.0
  Se  Se3  2  -0.0  0.0  0.92  1.0

Mg Rh Rh Se
MgRh2Se is Cyanogen Chloride-like structured and crystallizes in the monoclinic Cm space group. The structure is zero-dimensional and consists of two MgRh2Se clusters. Mg(1) is bonded in a linear geometry to one Rh(1) and one Se(1) atom. The Mg(1)-Rh(1) bond length is 0.84 Å. The Mg(1)-Se(1) bond length is 0.70 Å. There are two inequivalent Rh sites. In the first Rh site, Rh(1) is bonded in a single-bond geometry to one Mg(1) atom. In the second Rh site, Rh(2) is bonded in a single-bond geometry to one Se(1) atom. The Rh(2)-Se(1) bond length is 1.53 Å. Se(1) is bonded in a distorted single-bond geometry to one Mg(1) and one Rh(2) atom.