data_BaNp2Cu
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.2
_cell_length_b   5.2
_cell_length_c   5.2
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   BaNp2Cu
_chemical_formula_sum   'Ba1 Np2 Cu1'
_cell_volume   99.16
_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  0.67  0.67  0.67  1.0
  Np  Np2  1  0.84  0.84  0.84  1.0
  Np  Np3  1  0.51  0.51  0.51  1.0
  Cu  Cu1  1  0.0  0.0  0.0  1.0

data_BaNp2Cu
_symmetry_space_group_name_H-M   R3m
_cell_length_a   5.2
_cell_length_b   5.2
_cell_length_c   12.73
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   BaNp2Cu
_chemical_formula_sum   'Ba3 Np6 Cu3'
_cell_volume   297.49
_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
  Ba  Ba0  3  0.0  0.0  0.33  1.0
  Np  Np1  3  0.0  0.0  0.16  1.0
  Np  Np2  3  0.0  0.0  0.49  1.0
  Cu  Cu3  3  0.0  0.0  0.0  1.0

Ba Np Np Cu
BaNp2Cu crystallizes in the trigonal R3m space group. Ba(1) is bonded to one Np(1), one Np(2), and three equivalent Cu(1) atoms to form distorted BaNp2Cu3 trigonal bipyramids that share corners with six equivalent Ba(1)Np2Cu3 trigonal bipyramids and  a cornercorner with one Cu(1)Ba3Np trigonal pyramid. The Ba(1)-Np(1) bond length is 2.08 Å. The Ba(1)-Np(2) bond length is 2.08 Å. All Ba(1)-Cu(1) bond lengths are 3.00 Å. There are two inequivalent Np sites. In the first Np site, Np(1) is bonded in a linear geometry to one Ba(1) and one Cu(1) atom. The Np(1)-Cu(1) bond length is 2.08 Å. In the second Np site, Np(2) is bonded in a single-bond geometry to one Ba(1) atom. Cu(1) is bonded to three equivalent Ba(1) and one Np(1) atom to form distorted CuBa3Np trigonal pyramids that share  a cornercorner with one Ba(1)Np2Cu3 trigonal bipyramid and corners with six equivalent Cu(1)Ba3Np trigonal pyramids.