data_Mn2AlCu
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.05
_cell_length_b   4.05
_cell_length_c   4.05
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Mn2AlCu
_chemical_formula_sum   'Mn2 Al1 Cu1'
_cell_volume   46.91
_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
  Mn  Mn2  1  0.86  0.86  0.86  1.0
  Mn  Mn3  1  0.43  0.43  0.43  1.0
  Al  Al0  1  0.0  0.0  0.0  1.0
  Cu  Cu1  1  0.29  0.29  0.29  1.0

data_Mn2AlCu
_symmetry_space_group_name_H-M   R3m
_cell_length_a   4.05
_cell_length_b   4.05
_cell_length_c   9.92
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   Mn2AlCu
_chemical_formula_sum   'Mn6 Al3 Cu3'
_cell_volume   140.74
_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
  Mn  Mn0  3  0.0  0.0  0.14  1.0
  Mn  Mn1  3  0.0  0.0  0.57  1.0
  Al  Al2  3  0.0  0.0  0.0  1.0
  Cu  Cu3  3  0.0  0.0  0.71  1.0

Mn Mn Al Cu
Mn2CuAl is alpha As structured and crystallizes in the trigonal R3m space group. The structure is zero-dimensional and consists of three CuMn clusters and three MnAl clusters. In each CuMn cluster, Mn(2) is bonded in a single-bond geometry to one Cu(1) atom. The Mn(2)-Cu(1) bond length is 1.36 Å. Cu(1) is bonded in a single-bond geometry to one Mn(2) atom. In each MnAl cluster, Mn(1) is bonded in a single-bond geometry to one Al(1) atom. The Mn(1)-Al(1) bond length is 1.36 Å. Al(1) is bonded in a distorted single-bond geometry to one Mn(1) atom.