data_CaNbAs
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.59
_cell_length_b   4.59
_cell_length_c   4.59
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   CaNbAs
_chemical_formula_sum   'Ca1 Nb1 As1'
_cell_volume   68.36
_cell_formula_units_Z   1
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
  Ca  Ca1  1  0.0  0.0  0.0  1.0
  Nb  Nb2  1  0.25  0.25  0.25  1.0
  As  As0  1  0.87  0.87  0.87  1.0

data_CaNbAs
_symmetry_space_group_name_H-M   R3m
_cell_length_a   4.59
_cell_length_b   4.59
_cell_length_c   11.24
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   CaNbAs
_chemical_formula_sum   'Ca3 Nb3 As3'
_cell_volume   205.09
_cell_formula_units_Z   3
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
  Ca  Ca0  3  0.0  0.0  0.0  1.0
  Nb  Nb1  3  0.0  0.0  0.75  1.0
  As  As2  3  0.0  0.0  0.13  1.0

Ca Nb As
Ca Nb As 0 2 - - - 0 1 o o o 0 1 o o - 0 1 - o o 0 1 o - o 1 2 - - o 1 2 - o - 1 2 o - - 
CaNbAs crystallizes in the trigonal R3m space group. Ca(1) is bonded in a single-bond geometry to four equivalent Nb(1) and one As(1) atom. There is one shorter (2.76 Å) and three longer (2.83 Å) Ca(1)-Nb(1) bond lengths. The Ca(1)-As(1) bond length is 1.48 Å. Nb(1) is bonded to four equivalent Ca(1) and three equivalent As(1) atoms to form a mixture of distorted corner and edge-sharing NbCa4As3 hexagonal pyramids. All Nb(1)-As(1) bond lengths are 2.70 Å. As(1) is bonded in a single-bond geometry to one Ca(1) and three equivalent Nb(1) atoms.