data_Ta2BeCr
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.7
_cell_length_b   2.7
_cell_length_c   7.97
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Ta2BeCr
_chemical_formula_sum   'Ta2 Be1 Cr1'
_cell_volume   58.1
_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
  Ta  Ta2  1  0.0  0.0  0.84  1.0
  Ta  Ta3  1  0.35  0.35  0.32  1.0
  Be  Be0  1  0.0  0.0  0.13  1.0
  Cr  Cr1  1  0.35  0.35  0.64  1.0

data_Ta2BeCr
_symmetry_space_group_name_H-M   Cm
_cell_length_a   3.82
_cell_length_b   3.82
_cell_length_c   7.97
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   Ta2BeCr
_chemical_formula_sum   'Ta4 Be2 Cr2'
_cell_volume   116.21
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  'x, -y, z'
  3  'x+1/2, y+1/2, z'
  4  '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
  Ta  Ta0  2  0.0  0.0  0.84  1.0
  Ta  Ta1  2  0.35  0.0  0.32  1.0
  Be  Be2  2  0.0  0.0  0.13  1.0
  Cr  Cr3  2  0.35  0.0  0.64  1.0

Ta Ta Be Cr
Ta Ta Be Cr 0 3 - o o 0 3 o - o 0 3 o o o 0 0 + o o 0 0 o + o 0 2 o o + 1 2 o o o 1 2 o + o 1 2 + o o 1 1 + o o 1 1 o + o 1 3 o o o 2 2 + o o 2 2 o + o 3 3 + o o 3 3 o + o 
BeTa2Cr crystallizes in the monoclinic Cm space group. Be(1) is bonded in a 2-coordinate geometry to one Ta(1) and one Ta(2) atom. The Be(1)-Ta(1) bond length is 2.29 Å. The Be(1)-Ta(2) bond length is 2.07 Å. There are two inequivalent Ta sites. In the first Ta site, Ta(1) is bonded in a 9-coordinate geometry to one Be(1), four equivalent Ta(1), and four equivalent Cr(1) atoms. All Ta(1)-Ta(1) bond lengths are 2.70 Å. There are a spread of Ta(1)-Cr(1) bond distances ranging from 2.10-2.96 Å. In the second Ta site, Ta(2) is bonded in a 2-coordinate geometry to one Be(1) and one Cr(1) atom. The Ta(2)-Cr(1) bond length is 2.48 Å. Cr(1) is bonded in a 9-coordinate geometry to one Ta(2), four equivalent Ta(1), and four equivalent Cr(1) atoms. All Cr(1)-Cr(1) bond lengths are 2.70 Å.