data_Ba2MnCu
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.74
_cell_length_b   6.74
_cell_length_c   6.74
_cell_angle_alpha   138.96
_cell_angle_beta   138.96
_cell_angle_gamma   59.44
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Ba2MnCu
_chemical_formula_sum   'Ba2 Mn1 Cu1'
_cell_volume   130.7
_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
  Ba  Ba0  1  0.36  0.0  0.93  1.0
  Ba  Ba1  1  0.0  0.0  0.85  1.0
  Mn  Mn3  1  0.0  0.0  0.0  1.0
  Cu  Cu2  1  0.0  0.36  0.93  1.0

data_Ba2MnCu
_symmetry_space_group_name_H-M   P1
_cell_length_a   4.73
_cell_length_b   4.73
_cell_length_c   6.74
_cell_angle_alpha   110.52
_cell_angle_beta   110.52
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Ba2MnCu
_chemical_formula_sum   'Ba2 Mn1 Cu1'
_cell_volume   130.7
_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
  Ba  Ba0  1  0.07  0.0  0.44  1.0
  Ba  Ba1  1  0.15  0.0  0.15  1.0
  Mn  Mn2  1  0.0  0.0  0.0  1.0
  Cu  Cu3  1  0.44  0.36  0.44  1.0

Ba Ba Mn Cu
Ba Ba Mn Cu 0 3 o o o 0 1 o o o 1 2 o o + 1 3 o o o 
Ba2MnCu crystallizes in the triclinic P1 space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 5-coordinate geometry to one Ba(2), one Mn(1), and three equivalent Cu(1) atoms. The Ba(1)-Ba(2) bond length is 2.10 Å. The Ba(1)-Mn(1) bond length is 3.94 Å. There is one shorter (2.42 Å) and two longer (3.47 Å) Ba(1)-Cu(1) bond lengths. In the second Ba site, Ba(2) is bonded in a 2-coordinate geometry to one Ba(1), one Mn(1), and one Cu(1) atom. The Ba(2)-Mn(1) bond length is 0.99 Å. The Ba(2)-Cu(1) bond length is 2.10 Å. Mn(1) is bonded in a single-bond geometry to one Ba(1) and one Ba(2) atom. Cu(1) is bonded in a 4-coordinate geometry to one Ba(2) and three equivalent Ba(1) atoms.