The crystal structure described by Nb4Cr2Si5 crystallizes in the orthorhombic Ibam space group. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded in a 7-coordinate geometry to one Si(3), two equivalent Si(1), and four equivalent Si(2) atoms. In the second Nb site, Nb(2) is bonded in a 7-coordinate geometry to one Si(2), two equivalent Si(1), and four equivalent Si(3) atoms. Cr(1) is bonded in a 8-coordinate geometry to two equivalent Cr(1), two equivalent Si(2), and four equivalent Si(3) atoms. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded in a 10-coordinate geometry to four equivalent Nb(1), four equivalent Nb(2), and two equivalent Si(1) atoms. In the second Si site, Si(2) is bonded in a 10-coordinate geometry to one Nb(2), four equivalent Nb(1), two equivalent Cr(1), and three equivalent Si(2) atoms. In the third Si site, Si(3) is bonded in a 11-coordinate geometry to one Nb(1), four equivalent Nb(2), four equivalent Cr(1), and two equivalent Si(3) atoms. is represented by the CIF file [CIF]
data_Nb4Cr2Si5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.386
_cell_length_b   9.386
_cell_length_c   9.386
_cell_angle_alpha   149.366
_cell_angle_beta   130.272
_cell_angle_gamma   59.545
_symmetry_Int_Tables_number   1
_cell_volume   318.853
_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
  Nb  Nb0  1  0.192  0.936  0.256  1.0
  Nb  Nb1  1  0.808  0.064  0.744  1.0
  Nb  Nb2  1  0.319  0.564  0.756  1.0
  Nb  Nb3  1  0.681  0.436  0.244  1.0
  Nb  Nb4  1  0.030  0.643  0.386  1.0
  Nb  Nb5  1  0.970  0.357  0.614  1.0
  Nb  Nb6  1  0.743  0.857  0.886  1.0
  Nb  Nb7  1  0.257  0.143  0.114  1.0
  Cr  Cr8  1  0.693  0.943  0.250  1.0
  Cr  Cr9  1  0.307  0.557  0.250  1.0
  Cr  Cr10  1  0.307  0.057  0.750  1.0
  Cr  Cr11  1  0.693  0.443  0.750  1.0
  Si  Si12  1  0.000  0.250  0.250  1.0
  Si  Si13  1  0.000  0.750  0.750  1.0
  Si  Si14  1  0.652  0.570  0.082  1.0
  Si  Si15  1  0.348  0.430  0.918  1.0
  Si  Si16  1  0.512  0.930  0.582  1.0
  Si  Si17  1  0.488  0.070  0.418  1.0
  Si  Si18  1  0.988  0.782  0.206  1.0
  Si  Si19  1  0.012  0.218  0.794  1.0
  Si  Si20  1  0.576  0.282  0.294  1.0
  Si  Si21  1  0.424  0.718  0.706  1.0
[/CIF]
.
The crystal structure described by Nb4Cr2Si5 crystallizes in the orthorhombic Ibam space group. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded in a 7-coordinate geometry to one Si(3), two equivalent Si(1), and four equivalent Si(2) atoms. In the second Nb site, Nb(2) is bonded in a 7-coordinate geometry to one Si(2), two equivalent Si(1), and four equivalent Si(3) atoms. Cr(1) is bonded in a 8-coordinate geometry to two equivalent Cr(1), two equivalent Si(2), and four equivalent Si(3) atoms. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded in a 10-coordinate geometry to four equivalent Nb(1), four equivalent Nb(2), and two equivalent Si(1) atoms. In the second Si site, Si(2) is bonded in a 10-coordinate geometry to one Nb(2), four equivalent Nb(1), two equivalent Cr(1), and three equivalent Si(2) atoms. In the third Si site, Si(3) is bonded in a 11-coordinate geometry to one Nb(1), four equivalent Nb(2), four equivalent Cr(1), and two equivalent Si(3) atoms. is represented by the CIF file [CIF]
data_Nb4Cr2Si5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.386
_cell_length_b   9.386
_cell_length_c   9.386
_cell_angle_alpha   149.366
_cell_angle_beta   130.272
_cell_angle_gamma   59.545
_symmetry_Int_Tables_number   1
_cell_volume   318.853
_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
  Nb  Nb0  1  0.192  0.936  0.256  1.0
  Nb  Nb1  1  0.808  0.064  0.744  1.0
  Nb  Nb2  1  0.319  0.564  0.756  1.0
  Nb  Nb3  1  0.681  0.436  0.244  1.0
  Nb  Nb4  1  0.030  0.643  0.386  1.0
  Nb  Nb5  1  0.970  0.357  0.614  1.0
  Nb  Nb6  1  0.743  0.857  0.886  1.0
  Nb  Nb7  1  0.257  0.143  0.114  1.0
  Cr  Cr8  1  0.693  0.943  0.250  1.0
  Cr  Cr9  1  0.307  0.557  0.250  1.0
  Cr  Cr10  1  0.307  0.057  0.750  1.0
  Cr  Cr11  1  0.693  0.443  0.750  1.0
  Si  Si12  1  0.000  0.250  0.250  1.0
  Si  Si13  1  0.000  0.750  0.750  1.0
  Si  Si14  1  0.652  0.570  0.082  1.0
  Si  Si15  1  0.348  0.430  0.918  1.0
  Si  Si16  1  0.512  0.930  0.582  1.0
  Si  Si17  1  0.488  0.070  0.418  1.0
  Si  Si18  1  0.988  0.782  0.206  1.0
  Si  Si19  1  0.012  0.218  0.794  1.0
  Si  Si20  1  0.576  0.282  0.294  1.0
  Si  Si21  1  0.424  0.718  0.706  1.0
[/CIF]
.