data_EuSi2Ni
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.57
_cell_length_b   4.57
_cell_length_c   4.57
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   EuSi2Ni
_chemical_formula_sum   'Eu1 Si2 Ni1'
_cell_volume   67.3
_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
  Eu  Eu0  1  0.23  0.23  0.23  1.0
  Si  Si2  1  0.61  0.61  0.61  1.0
  Si  Si3  1  0.84  0.84  0.84  1.0
  Ni  Ni1  1  0.0  0.0  0.0  1.0

data_EuSi2Ni
_symmetry_space_group_name_H-M   R3m
_cell_length_a   4.57
_cell_length_b   4.57
_cell_length_c   11.18
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   EuSi2Ni
_chemical_formula_sum   'Eu3 Si6 Ni3'
_cell_volume   201.89
_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
  Eu  Eu0  3  0.0  0.0  0.77  1.0
  Si  Si1  3  0.0  0.0  0.16  1.0
  Si  Si2  3  0.0  0.0  0.39  1.0
  Ni  Ni3  3  0.0  0.0  0.0  1.0

Eu Si Si Ni
EuNiSi2 crystallizes in the trigonal R3m space group. Eu(1) is bonded in a 10-coordinate geometry to four equivalent Ni(1), three equivalent Si(1), and three equivalent Si(2) atoms. There is one shorter (2.55 Å) and three longer (2.89 Å) Eu(1)-Ni(1) bond lengths. All Eu(1)-Si(1) bond lengths are 2.70 Å. All Eu(1)-Si(2) bond lengths are 2.70 Å. Ni(1) is bonded in a distorted linear geometry to four equivalent Eu(1), one Si(2), and three equivalent Si(1) atoms. The Ni(1)-Si(2) bond length is 1.76 Å. All Ni(1)-Si(1) bond lengths are 2.70 Å. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a 7-coordinate geometry to three equivalent Eu(1), three equivalent Ni(1), and one Si(2) atom. The Si(1)-Si(2) bond length is 2.55 Å. In the second Si site, Si(2) is bonded in a 5-coordinate geometry to three equivalent Eu(1), one Ni(1), and one Si(1) atom.