data_CoB2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.87
_cell_length_b   3.87
_cell_length_c   3.87
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   CoB2
_chemical_formula_sum   'Co2 B4'
_cell_volume   41.07
_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
  Co  Co4  1  0.0  0.0  0.0  1.0
  Co  Co5  1  0.37  0.37  0.37  1.0
  B  B0  1  0.05  0.05  0.42  1.0
  B  B1  1  0.42  0.05  0.05  1.0
  B  B2  1  0.05  0.42  0.05  1.0
  B  B3  1  0.42  0.42  0.42  1.0

data_CoB2
_symmetry_space_group_name_H-M   R3m
_cell_length_a   3.87
_cell_length_b   3.87
_cell_length_c   9.49
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   CoB2
_chemical_formula_sum   'Co6 B12'
_cell_volume   123.21
_cell_formula_units_Z   6
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  '-y, x-y, z'
  3  '-x+y, -x, z'
  4  '-y, -x, z'
  5  '-x+y, y, z'
  6  'x, x-y, z'
  7  'x+1/3, y+2/3, z+2/3'
  8  '-y+1/3, x-y+2/3, z+2/3'
  9  '-x+y+1/3, -x+2/3, z+2/3'
  10  '-y+1/3, -x+2/3, z+2/3'
  11  '-x+y+1/3, y+2/3, z+2/3'
  12  'x+1/3, x-y+2/3, z+2/3'
  13  'x+2/3, y+1/3, z+1/3'
  14  '-y+2/3, x-y+1/3, z+1/3'
  15  '-x+y+2/3, -x+1/3, z+1/3'
  16  '-y+2/3, -x+1/3, z+1/3'
  17  '-x+y+2/3, y+1/3, z+1/3'
  18  'x+2/3, x-y+1/3, z+1/3'
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
  Co  Co0  3  0.0  0.0  0.0  1.0
  Co  Co1  3  0.0  0.0  0.63  1.0
  B  B2  9  0.09  0.54  0.49  1.0
  B  B3  3  0.0  0.0  0.58  1.0

Co Co B B B B
Co Co B B B B 0 4 o - o 0 4 o o o 0 3 - o o 0 3 o o o 0 1 - o o 0 1 o - o 0 1 o o - 0 2 o o - 0 2 o o o 1 5 o o o 2 4 o o o 2 3 o o o 3 4 o o o 
CoB2 crystallizes in the trigonal R3m space group. There are two inequivalent Co sites. In the first Co site, Co(1) is bonded in a 6-coordinate geometry to six equivalent B(1) atoms. There are three shorter (1.87 Å) and three longer (2.05 Å) Co(1)-B(1) bond lengths. In the second Co site, Co(2) is bonded in a single-bond geometry to one B(2) and three equivalent B(1) atoms. The Co(2)-B(2) bond length is 0.51 Å. All Co(2)-B(1) bond lengths are 2.00 Å. There are two inequivalent B sites. In the first B site, B(1) is bonded in a 7-coordinate geometry to one Co(2), two equivalent Co(1), two equivalent B(1), and two equivalent B(2) atoms. Both B(1)-B(1) bond lengths are 1.43 Å. Both B(1)-B(2) bond lengths are 2.13 Å. In the second B site, B(2) is bonded in a single-bond geometry to one Co(2) and six equivalent B(1) atoms.