data_GaC2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.41
_cell_length_b   4.41
_cell_length_c   4.41
_cell_angle_alpha   113.7
_cell_angle_beta   113.7
_cell_angle_gamma   101.31
_symmetry_Int_Tables_number   1
_chemical_formula_structural   GaC2
_chemical_formula_sum   'Ga2 C4'
_cell_volume   64.94
_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
  Ga  Ga4  1  0.0  0.0  0.19  1.0
  Ga  Ga5  1  0.0  0.0  0.4  1.0
  C  C0  1  0.46  0.95  0.0  1.0
  C  C1  1  0.95  0.46  0.79  1.0
  C  C2  1  0.87  0.46  0.0  1.0
  C  C3  1  0.54  0.95  0.79  1.0

data_GaC2
_symmetry_space_group_name_H-M   P1
_cell_length_a   4.41
_cell_length_b   4.41
_cell_length_c   4.41
_cell_angle_alpha   101.31
_cell_angle_beta   113.7
_cell_angle_gamma   113.7
_symmetry_Int_Tables_number   1
_chemical_formula_structural   GaC2
_chemical_formula_sum   'Ga2 C4'
_cell_volume   64.94
_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
  Ga  Ga0  1  0.19  0.19  0.19  1.0
  Ga  Ga1  1  0.4  0.4  0.4  1.0
  C  C2  1  -0.0  0.54  0.05  1.0
  C  C3  1  0.0  0.13  0.54  1.0
  C  C4  1  0.79  0.25  0.84  1.0
  C  C5  1  0.79  0.84  0.33  1.0

Ga Ga C C C C
Ga Ga C C C C 0 1 o o o 2 5 o o - 3 4 o o + 
GaC2 crystallizes in the triclinic P1 space group. There are two inequivalent Ga sites. In the first Ga site, Ga(1) is bonded in a 7-coordinate geometry to one Ga(2), one C(2), one C(4), two equivalent C(1), and two equivalent C(3) atoms. The Ga(1)-Ga(2) bond length is 0.91 Å. The Ga(1)-C(2) bond length is 2.22 Å. The Ga(1)-C(4) bond length is 1.97 Å. There is one shorter (2.11 Å) and one longer (2.50 Å) Ga(1)-C(1) bond length. There is one shorter (2.04 Å) and one longer (2.57 Å) Ga(1)-C(3) bond length. In the second Ga site, Ga(2) is bonded in a 5-coordinate geometry to one Ga(1), one C(1), one C(2), one C(3), and one C(4) atom. The Ga(2)-C(1) bond length is 2.22 Å. The Ga(2)-C(2) bond length is 2.20 Å. The Ga(2)-C(3) bond length is 2.09 Å. The Ga(2)-C(4) bond length is 2.44 Å. There are four inequivalent C sites. In the first C site, C(1) is bonded in a 4-coordinate geometry to one Ga(2), two equivalent Ga(1), and one C(4) atom. The C(1)-C(4) bond length is 1.10 Å. In the second C site, C(2) is bonded in a 3-coordinate geometry to one Ga(1), one Ga(2), and one C(3) atom. The C(2)-C(3) bond length is 1.10 Å. In the third C site, C(3) is bonded in a 5-coordinate geometry to one Ga(2), two equivalent Ga(1), one C(2), and one C(4) atom. The C(3)-C(4) bond length is 2.00 Å. In the fourth C site, C(4) is bonded in a distorted see-saw-like geometry to one Ga(1), one Ga(2), one C(1), and one C(3) atom.