data_AcLaNi2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.05
_cell_length_b   5.05
_cell_length_c   5.05
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   AcLaNi2
_chemical_formula_sum   'Ac1 La1 Ni2'
_cell_volume   91.01
_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
  Ac  Ac0  1  0.57  0.57  0.57  1.0
  La  La1  1  0.0  0.0  0.0  1.0
  Ni  Ni2  1  0.36  0.36  0.36  1.0
  Ni  Ni3  1  0.79  0.79  0.79  1.0

data_AcLaNi2
_symmetry_space_group_name_H-M   R3m
_cell_length_a   5.05
_cell_length_b   5.05
_cell_length_c   12.37
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   AcLaNi2
_chemical_formula_sum   'Ac3 La3 Ni6'
_cell_volume   273.03
_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
  La  La0  3  0.0  0.0  0.0  1.0
  Ac  Ac1  3  0.0  0.0  0.43  1.0
  Ni  Ni2  3  0.0  0.0  0.21  1.0
  Ni  Ni3  3  0.0  0.0  0.64  1.0

Ac La Ni Ni
AcLaNi2 is Heusler structured and crystallizes in the trigonal R3m space group. Ac(1) is bonded in a distorted linear geometry to one Ni(2) and four equivalent Ni(1) atoms. The Ac(1)-Ni(2) bond length is 2.66 Å. There is one shorter (2.66 Å) and three longer (3.26 Å) Ac(1)-Ni(1) bond lengths. La(1) is bonded in a 4-coordinate geometry to one Ni(2) and three equivalent Ni(1) atoms. The La(1)-Ni(2) bond length is 2.66 Å. All La(1)-Ni(1) bond lengths are 2.93 Å. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a 7-coordinate geometry to four equivalent Ac(1) and three equivalent La(1) atoms. In the second Ni site, Ni(2) is bonded in a distorted linear geometry to one Ac(1) and one La(1) atom.