data_BeSi2Ni
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.39
_cell_length_b   4.39
_cell_length_c   4.39
_cell_angle_alpha   132.4
_cell_angle_beta   132.4
_cell_angle_gamma   69.6
_symmetry_Int_Tables_number   1
_chemical_formula_structural   BeSi2Ni
_chemical_formula_sum   'Be1 Si2 Ni1'
_cell_volume   45.19
_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
  Be  Be0  1  0.0  0.0  0.0  1.0
  Si  Si2  1  0.0  0.0  0.6  1.0
  Si  Si3  1  0.0  0.77  0.8  1.0
  Ni  Ni1  1  0.77  0.0  0.8  1.0

data_BeSi2Ni
_symmetry_space_group_name_H-M   P1
_cell_length_a   3.54
_cell_length_b   3.54
_cell_length_c   4.39
_cell_angle_alpha   113.8
_cell_angle_beta   113.8
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   BeSi2Ni
_chemical_formula_sum   'Be1 Si2 Ni1'
_cell_volume   45.19
_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
  Be  Be0  1  0.0  0.0  0.0  1.0
  Si  Si1  1  0.4  0.0  0.4  1.0
  Si  Si2  1  0.97  0.77  0.97  1.0
  Ni  Ni3  1  0.2  0.0  0.97  1.0

Be Si Si Ni
Be Si Si Ni 0 3 - o - 0 2 o - - 0 1 o o - 1 3 - o o 1 2 o - o 
BeNiSi2 crystallizes in the triclinic P1 space group. Be(1) is bonded in an L-shaped geometry to one Ni(1), one Si(2), and two equivalent Si(1) atoms. The Be(1)-Ni(1) bond length is 0.77 Å. The Be(1)-Si(2) bond length is 0.77 Å. There is one shorter (1.74 Å) and one longer (2.65 Å) Be(1)-Si(1) bond length. Ni(1) is bonded in a single-bond geometry to one Be(1) and two equivalent Si(1) atoms. There is one shorter (1.72 Å) and one longer (2.87 Å) Ni(1)-Si(1) bond length. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a 6-coordinate geometry to two equivalent Be(1), two equivalent Ni(1), and two equivalent Si(2) atoms. There is one shorter (1.72 Å) and one longer (2.87 Å) Si(1)-Si(2) bond length. In the second Si site, Si(2) is bonded in a single-bond geometry to one Be(1) and two equivalent Si(1) atoms.