data_As2C
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.83
_cell_length_b   6.83
_cell_length_c   6.69
_cell_angle_alpha   116.52
_cell_angle_beta   116.52
_cell_angle_gamma   25.6
_symmetry_Int_Tables_number   1
_chemical_formula_structural   As2C
_chemical_formula_sum   'As4 C2'
_cell_volume   119.95
_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
  As  As0  1  0.3  0.0  0.02  1.0
  As  As1  1  0.97  0.0  0.92  1.0
  As  As2  1  0.67  0.0  0.77  1.0
  As  As3  1  0.6  0.0  0.17  1.0
  C  C4  1  0.99  0.0  0.15  1.0
  C  C5  1  0.27  0.0  0.8  1.0

data_As2C
_symmetry_space_group_name_H-M   P-1
_cell_length_a   3.03
_cell_length_b   6.69
_cell_length_c   6.83
_cell_angle_alpha   116.52
_cell_angle_beta   102.8
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   2
_chemical_formula_structural   As2C
_chemical_formula_sum   'As4 C2'
_cell_volume   119.95
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  '-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
  As  As0  2  0.0  0.3  0.53  1.0
  As  As1  2  0.0  0.45  0.83  1.0
  C  C2  2  0.0  0.32  0.14  1.0

As As As As C C
As As As As C C 0 5 o o - 0 3 o o o 1 4 o o + 1 2 o o o 
As2C crystallizes in the triclinic P-1 space group. The structure is zero-dimensional and consists of two monomethyl diarsane molecules. C(1) is bonded in a single-bond geometry to one As(1) atom. The C(1)-As(1) bond length is 1.46 Å. There are two inequivalent As sites. In the first As site, As(1) is bonded in a single-bond geometry to one C(1) and one As(2) atom. The As(1)-As(2) bond length is 1.83 Å. In the second As site, As(2) is bonded in a distorted single-bond geometry to one As(1) atom.