data_MgCrNi2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.48
_cell_length_b   8.48
_cell_length_c   8.48
_cell_angle_alpha   17.89
_cell_angle_beta   17.89
_cell_angle_gamma   17.89
_symmetry_Int_Tables_number   1
_chemical_formula_structural   MgCrNi2
_chemical_formula_sum   'Mg1 Cr1 Ni2'
_cell_volume   50.25
_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  0.0  1.0
  Cr  Cr0  1  0.0  0.0  0.51  1.0
  Ni  Ni2  1  0.0  0.0  0.89  1.0
  Ni  Ni3  1  0.0  0.0  0.14  1.0

data_MgCrNi2
_symmetry_space_group_name_H-M   Cm
_cell_length_a   4.57
_cell_length_b   2.64
_cell_length_c   8.48
_cell_angle_alpha   90.0
_cell_angle_beta   100.35
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   MgCrNi2
_chemical_formula_sum   'Mg2 Cr2 Ni4'
_cell_volume   100.49
_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  0.0  1.0
  Cr  Cr1  2  0.0  0.0  0.49  1.0
  Ni  Ni2  2  0.0  0.0  0.11  1.0
  Ni  Ni3  2  0.0  0.0  0.86  1.0

Mg Cr Ni Ni
Mg Cr Ni Ni 0 2 o o - 0 3 o o o 1 1 o + - 1 1 + - o 1 1 + o - 
MgCrNi2 crystallizes in the monoclinic Cm space group. Mg(1) is bonded in a linear geometry to one Ni(1) and one Ni(2) atom. The Mg(1)-Ni(1) bond length is 0.95 Å. The Mg(1)-Ni(2) bond length is 1.15 Å. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to six Cr(1,1); one Ni(1); and one Ni(2) atom to form a mixture of edge and corner-sharing CrCr6Ni2 hexagonal bipyramids. All Cr(1)-Cr(1,1) bond lengths are 2.64 Å. The Cr(1)-Ni(1) bond length is 3.19 Å. The Cr(1)-Ni(2) bond length is 3.19 Å. In the second Cr site, Cr(1) is bonded to six Cr(1,1); one Ni(1); and one Ni(2) atom to form a mixture of edge and corner-sharing CrCr6Ni2 hexagonal bipyramids. Both Cr(1)-Cr(1) bond lengths are 2.64 Å. The Cr(1)-Ni(1) bond length is 3.19 Å. The Cr(1)-Ni(2) bond length is 3.19 Å. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a single-bond geometry to one Mg(1) and one Cr(1) atom. In the second Ni site, Ni(2) is bonded in a single-bond geometry to one Mg(1) and one Cr(1) atom.