data_AgBSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.27
_cell_length_b   3.27
_cell_length_c   6.79
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   AgBSe2
_chemical_formula_sum   'Ag1 B1 Se2'
_cell_volume   72.54
_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
  Ag  Ag0  1  0.63  0.63  0.2  1.0
  B  B1  1  0.0  0.0  0.39  1.0
  Se  Se2  1  0.63  0.63  0.78  1.0
  Se  Se3  1  0.0  0.0  0.61  1.0

data_AgBSe2
_symmetry_space_group_name_H-M   Cm
_cell_length_a   4.62
_cell_length_b   4.62
_cell_length_c   6.79
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   AgBSe2
_chemical_formula_sum   'Ag2 B2 Se4'
_cell_volume   145.09
_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
  Ag  Ag0  2  0.13  0.5  0.2  1.0
  B  B1  2  0.0  0.0  0.39  1.0
  Se  Se2  2  0.0  0.0  0.61  1.0
  Se  Se3  2  0.13  0.5  0.78  1.0

Ag B Se Se
Ag B Se Se 0 1 + + o 1 3 o o o 2 3 + + o 
AgBSe2 crystallizes in the monoclinic Cm space group. Ag(1) is bonded in a 4-coordinate geometry to three equivalent B(1) and one Se(1) atom. There is one shorter (2.09 Å) and two longer (2.69 Å) Ag(1)-B(1) bond lengths. The Ag(1)-Se(1) bond length is 2.87 Å. B(1) is bonded in a distorted single-bond geometry to three equivalent Ag(1) and one Se(2) atom. The B(1)-Se(2) bond length is 1.50 Å. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a 4-coordinate geometry to one Ag(1) and three equivalent Se(2) atoms. There is one shorter (2.07 Å) and two longer (2.67 Å) Se(1)-Se(2) bond lengths. In the second Se site, Se(2) is bonded in a single-bond geometry to one B(1) and three equivalent Se(1) atoms.