The material described by B4C crystallizes in the trigonal R-3m space group. There are two inequivalent B sites. In the first B site, B(1) is bonded in a single-bond geometry to two equivalent B(2) and one C(1) atom. In the second B site, B(2) is bonded in a 4-coordinate geometry to two equivalent B(1) and two equivalent B(2) atoms. There are two inequivalent C sites. In the first C site, C(2) is bonded in a linear geometry to two equivalent C(1) atoms. In the second C site, C(1) is bonded to three equivalent B(1) and one C(2) atom to form distorted corner-sharing CB3C tetrahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_B4C
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.776
_cell_length_b   6.776
_cell_length_c   6.776
_cell_angle_alpha   60.412
_cell_angle_beta   60.412
_cell_angle_gamma   60.412
_symmetry_Int_Tables_number   1
_cell_volume   222.027
_cell_formula_units_Z   3
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
  B  B0  1  0.872  0.500  0.500  1.0
  B  B1  1  0.500  0.500  0.872  1.0
  B  B2  1  0.500  0.872  0.500  1.0
  B  B3  1  0.500  0.128  0.500  1.0
  B  B4  1  0.128  0.500  0.500  1.0
  B  B5  1  0.500  0.500  0.128  1.0
  B  B6  1  0.104  0.346  0.346  1.0
  B  B7  1  0.346  0.346  0.104  1.0
  B  B8  1  0.346  0.104  0.346  1.0
  B  B9  1  0.654  0.896  0.654  1.0
  B  B10  1  0.896  0.654  0.654  1.0
  B  B11  1  0.654  0.654  0.896  1.0
  C  C12  1  0.416  0.416  0.416  1.0
  C  C13  1  0.584  0.584  0.584  1.0
  C  C14  1  0.500  0.500  0.500  1.0
[/CIF]
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The material described by B4C crystallizes in the trigonal R-3m space group. There are two inequivalent B sites. In the first B site, B(1) is bonded in a single-bond geometry to two equivalent B(2) and one C(1) atom. In the second B site, B(2) is bonded in a 4-coordinate geometry to two equivalent B(1) and two equivalent B(2) atoms. There are two inequivalent C sites. In the first C site, C(2) is bonded in a linear geometry to two equivalent C(1) atoms. In the second C site, C(1) is bonded to three equivalent B(1) and one C(2) atom to form distorted corner-sharing CB3C tetrahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_B4C
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.776
_cell_length_b   6.776
_cell_length_c   6.776
_cell_angle_alpha   60.412
_cell_angle_beta   60.412
_cell_angle_gamma   60.412
_symmetry_Int_Tables_number   1
_cell_volume   222.027
_cell_formula_units_Z   3
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
  B  B0  1  0.872  0.500  0.500  1.0
  B  B1  1  0.500  0.500  0.872  1.0
  B  B2  1  0.500  0.872  0.500  1.0
  B  B3  1  0.500  0.128  0.500  1.0
  B  B4  1  0.128  0.500  0.500  1.0
  B  B5  1  0.500  0.500  0.128  1.0
  B  B6  1  0.104  0.346  0.346  1.0
  B  B7  1  0.346  0.346  0.104  1.0
  B  B8  1  0.346  0.104  0.346  1.0
  B  B9  1  0.654  0.896  0.654  1.0
  B  B10  1  0.896  0.654  0.654  1.0
  B  B11  1  0.654  0.654  0.896  1.0
  C  C12  1  0.416  0.416  0.416  1.0
  C  C13  1  0.584  0.584  0.584  1.0
  C  C14  1  0.500  0.500  0.500  1.0
[/CIF]
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