data_GeAs
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.38
_cell_length_b   3.38
_cell_length_c   6.75
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   GeAs
_chemical_formula_sum   'Ge2 As2'
_cell_volume   76.91
_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
  Ge  Ge2  1  0.69  0.0  0.52  1.0
  Ge  Ge3  1  0.0  0.69  0.23  1.0
  As  As0  1  0.69  0.0  0.91  1.0
  As  As1  1  0.0  0.69  0.84  1.0

data_GeAs
_symmetry_space_group_name_H-M   C2/m
_cell_length_a   4.77
_cell_length_b   4.77
_cell_length_c   6.75
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   12
_chemical_formula_structural   GeAs
_chemical_formula_sum   'Ge4 As4'
_cell_volume   153.81
_cell_formula_units_Z   4
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  '-x, -y, -z'
  3  '-x, y, -z'
  4  'x, -y, z'
  5  'x+1/2, y+1/2, z'
  6  '-x+1/2, -y+1/2, -z'
  7  '-x+1/2, y+1/2, -z'
  8  '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
  Ge  Ge0  4  0.16  0.0  0.85  1.0
  As  As1  4  0.16  0.0  0.46  1.0

Ge Ge As As
Ge Ge As As 0 1 + - o 0 3 + - o 0 2 o o o 1 2 - + - 1 3 o o - 2 3 + - o 
GeAs is gamma CuTi structured and crystallizes in the monoclinic C2/m space group. Ge(1) is bonded in a 3-coordinate geometry to one Ge(1) and two equivalent As(1) atoms. The Ge(1)-Ge(1) bond length is 2.47 Å. There is one shorter (2.60 Å) and one longer (2.65 Å) Ge(1)-As(1) bond length. As(1) is bonded in a 5-coordinate geometry to two equivalent Ge(1) and three equivalent As(1) atoms. There is one shorter (1.58 Å) and two longer (2.60 Å) As(1)-As(1) bond lengths.