data_ScMnSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.54
_cell_length_b   3.54
_cell_length_c   5.92
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   ScMnSe2
_chemical_formula_sum   'Sc1 Mn1 Se2'
_cell_volume   74.01
_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
  Sc  Sc1  1  0.0  0.0  0.63  1.0
  Mn  Mn0  1  0.77  0.77  0.78  1.0
  Se  Se2  1  0.77  0.77  0.36  1.0
  Se  Se3  1  0.0  0.0  0.02  1.0

data_ScMnSe2
_symmetry_space_group_name_H-M   Cm
_cell_length_a   5.0
_cell_length_b   5.0
_cell_length_c   5.92
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   ScMnSe2
_chemical_formula_sum   'Sc2 Mn2 Se4'
_cell_volume   148.02
_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
  Sc  Sc0  2  0.0  0.0  0.63  1.0
  Mn  Mn1  2  0.27  0.5  0.78  1.0
  Se  Se2  2  0.0  0.0  0.02  1.0
  Se  Se3  2  0.27  0.5  0.36  1.0

Sc Mn Se Se
Sc Mn Se Se 0 1 - - o 0 2 - - o 1 3 + + + 2 3 + + o 
ScMnSe2 crystallizes in the monoclinic Cm space group. The structure is zero-dimensional and consists of two ScMnSe2 clusters. Sc(1) is bonded in a distorted L-shaped geometry to one Mn(1) and one Se(1) atom. The Sc(1)-Mn(1) bond length is 1.47 Å. The Sc(1)-Se(1) bond length is 1.97 Å. Mn(1) is bonded in an L-shaped geometry to one Sc(1) and one Se(2) atom. The Mn(1)-Se(2) bond length is 1.80 Å. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a single-bond geometry to one Sc(1) atom. In the second Se site, Se(2) is bonded in a distorted single-bond geometry to one Mn(1) atom.