data_NaCrHg2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.06
_cell_length_b   5.06
_cell_length_c   3.33
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   NaCrHg2
_chemical_formula_sum   'Na1 Cr1 Hg2'
_cell_volume   85.38
_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
  Na  Na3  1  0.0  0.0  0.0  1.0
  Cr  Cr0  1  0.53  0.53  0.0  1.0
  Hg  Hg1  1  0.53  0.0  0.67  1.0
  Hg  Hg2  1  0.0  0.53  0.67  1.0

data_NaCrHg2
_symmetry_space_group_name_H-M   Cm
_cell_length_a   7.16
_cell_length_b   7.16
_cell_length_c   3.33
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   NaCrHg2
_chemical_formula_sum   'Na2 Cr2 Hg4'
_cell_volume   170.76
_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
  Na  Na0  2  0.0  0.0  0.0  1.0
  Cr  Cr1  2  0.03  0.5  -0.0  1.0
  Hg  Hg2  4  0.27  0.27  0.67  1.0

Na Cr Hg Hg
Na Cr Hg Hg 0 1 - - o 0 2 - o - 0 2 - o o 0 2 o o - 0 3 o - - 0 3 o - o 0 3 o o - 0 0 o o + 1 3 o o - 1 3 + o - 1 3 + o o 1 2 o o - 1 2 o + - 1 2 o + o 1 1 o o + 2 3 + - o 2 2 o o + 3 3 o o + 
NaCrHg2 crystallizes in the monoclinic Cm space group. Na(1) is bonded in a 4-coordinate geometry to eight equivalent Hg(1) atoms. There are a spread of Na(1)-Hg(1) bond distances ranging from 2.62-3.49 Å. Cr(1) is bonded in a 4-coordinate geometry to six equivalent Hg(1) atoms. There are a spread of Cr(1)-Hg(1) bond distances ranging from 2.62-3.25 Å. Hg(1) is bonded in a 7-coordinate geometry to four equivalent Na(1) and three equivalent Cr(1) atoms.