data_NbCrSi4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.81
_cell_length_b   4.81
_cell_length_c   4.81
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   NbCrSi4
_chemical_formula_sum   'Nb1 Cr1 Si4'
_cell_volume   78.86
_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
  Nb  Nb1  1  0.7  0.7  0.7  1.0
  Cr  Cr0  1  0.0  0.0  0.0  1.0
  Si  Si2  1  0.55  0.55  0.26  1.0
  Si  Si3  1  0.55  0.26  0.55  1.0
  Si  Si4  1  0.26  0.55  0.55  1.0
  Si  Si5  1  0.26  0.26  0.26  1.0

data_NbCrSi4
_symmetry_space_group_name_H-M   R3m
_cell_length_a   4.81
_cell_length_b   4.81
_cell_length_c   11.79
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   NbCrSi4
_chemical_formula_sum   'Nb3 Cr3 Si12'
_cell_volume   236.59
_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
  Nb  Nb0  3  0.0  0.0  0.3  1.0
  Cr  Cr1  3  0.0  0.0  0.0  1.0
  Si  Si2  9  0.2  0.1  0.55  1.0
  Si  Si3  3  0.0  0.0  0.74  1.0

Nb Cr Si Si Si Si
Nb Cr Si Si Si Si 0 2 o o + 0 4 + o o 0 3 o + o 0 1 + + o 0 1 + o + 0 1 o + + 0 5 + o o 0 5 o + o 0 5 o o + 1 2 - - o 1 2 - o o 1 2 o - o 1 3 - o - 1 3 - o o 1 3 o o - 1 5 - o o 1 5 o - o 1 5 o o - 1 5 o o o 1 4 o - - 1 4 o - o 1 4 o o - 2 3 o o o 2 4 o o o 2 5 + o o 2 5 o + o 2 5 o o o 3 4 o o o 3 5 + o o 3 5 o o + 3 5 o o o 4 5 o + o 4 5 o o + 4 5 o o o 
NbCrSi4 crystallizes in the trigonal R3m space group. Nb(1) is bonded in a distorted trigonal non-coplanar geometry to three equivalent Cr(1), three equivalent Si(1), and three equivalent Si(2) atoms. All Nb(1)-Cr(1) bond lengths are 2.81 Å. All Nb(1)-Si(1) bond lengths are 2.20 Å. All Nb(1)-Si(2) bond lengths are 3.08 Å. Cr(1) is bonded in a 16-coordinate geometry to three equivalent Nb(1), four equivalent Si(2), and nine equivalent Si(1) atoms. There are three shorter (2.92 Å) and one longer (3.03 Å) Cr(1)-Si(2) bond length. There are six shorter (2.85 Å) and three longer (3.20 Å) Cr(1)-Si(1) bond lengths. There are two inequivalent Si sites. In the first Si site, Si(2) is bonded in a 10-coordinate geometry to three equivalent Nb(1), four equivalent Cr(1), and three equivalent Si(1) atoms. All Si(2)-Si(1) bond lengths are 2.45 Å. In the second Si site, Si(1) is bonded in a 3-coordinate geometry to one Nb(1), three equivalent Cr(1), one Si(2), and two equivalent Si(1) atoms. Both Si(1)-Si(1) bond lengths are 1.41 Å.