data_MgCrNi2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.94
_cell_length_b   2.94
_cell_length_c   5.97
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   MgCrNi2
_chemical_formula_sum   'Mg1 Cr1 Ni2'
_cell_volume   51.73
_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
  Mg  Mg1  1  0.0  0.0  0.56  1.0
  Cr  Cr0  1  0.47  0.47  0.67  1.0
  Ni  Ni2  1  0.47  0.47  0.19  1.0
  Ni  Ni3  1  0.0  0.0  0.53  1.0

data_MgCrNi2
_symmetry_space_group_name_H-M   Cm
_cell_length_a   4.16
_cell_length_b   4.16
_cell_length_c   5.97
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   MgCrNi2
_chemical_formula_sum   'Mg2 Cr2 Ni4'
_cell_volume   103.47
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  'x, -y, z'
  3  'x+1/2, y+1/2, z'
  4  'x+1/2, -y+1/2, 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
  Mg  Mg0  2  0.0  0.0  0.56  1.0
  Cr  Cr1  2  0.47  0.0  0.67  1.0
  Ni  Ni2  2  0.0  0.0  0.53  1.0
  Ni  Ni3  2  0.47  0.0  0.19  1.0

Mg Cr Ni Ni
MgCrNi2 crystallizes in the monoclinic Cm space group. Mg(1) is bonded in a single-bond geometry to four equivalent Cr(1) and one Ni(2) atom. There are a spread of Mg(1)-Cr(1) bond distances ranging from 2.09-2.31 Å. The Mg(1)-Ni(2) bond length is 0.15 Å. Cr(1) is bonded in a 5-coordinate geometry to four equivalent Mg(1) and two equivalent Ni(1) atoms. There is one shorter (2.86 Å) and one longer (3.11 Å) Cr(1)-Ni(1) bond length. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a 10-coordinate geometry to two equivalent Cr(1), four equivalent Ni(1), and four equivalent Ni(2) atoms. All Ni(1)-Ni(1) bond lengths are 2.94 Å. There are a spread of Ni(1)-Ni(2) bond distances ranging from 2.81-2.98 Å. In the second Ni site, Ni(2) is bonded in a single-bond geometry to one Mg(1) and four equivalent Ni(1) atoms.