data_1010643
_chemical_name_systematic          'Mercury iodide'
_chemical_formula_structural       'Hg I2'
_chemical_formula_sum              'Hg I2'
_publ_section_title
;
De kristalstructuur van rood mercuri-iodide. Onderzoekingen over
verstrooiende vermogens in het bijzonder van zuurstof
;
_publ_author_name                  'Claassen, A F P J'
_journal_name_full                 'Thesis, Univ. Amsterdam'
_journal_coden_ASTM                UANLTX
_journal_volume                    1926
_journal_year                      1926
_journal_page_first                1
_journal_page_last                 78
_cell_length_a                     4.357
_cell_length_b                     4.357
_cell_length_c                     12.36
_cell_angle_alpha                  90
_cell_angle_beta                   90
_cell_angle_gamma                  90
_cell_volume                       234.6
_cell_formula_units_Z              2
_symmetry_space_group_name_H-M     'P 42/n m c S'
_symmetry_Int_Tables_number        137
_symmetry_cell_setting             tetragonal
loop_
_symmetry_equiv_pos_as_xyz
  'x,y,z'
  '-x,-y,z'
  '1/2+x,1/2+y,1/2-z'
  '1/2-x,1/2-y,1/2-z'
  '-x,y,z'
  'x,-y,z'
  '1/2-x,1/2+y,1/2-z'
  '1/2+x,1/2-y,1/2-z'
  '-y,x,-z'
  'y,-x,-z'
  '1/2-y,1/2+x,1/2+z'
  '1/2+y,1/2-x,1/2+z'
  'y,x,-z'
  '-y,-x,-z'
  '1/2+y,1/2+x,1/2+z'
  '1/2-y,1/2-x,1/2+z'
loop_
_atom_type_symbol
_atom_type_oxidation_number
  Hg2+   2.000
  I1-   -1.000
loop_
_atom_site_label
_atom_site_type_symbol
_atom_site_symmetry_multiplicity
_atom_site_Wyckoff_symbol
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_occupancy
_atom_site_attached_hydrogens
_atom_site_calc_flag
  Hg1   Hg2+   2 a 0. 0. 0. 1.  0 d
  I1    I1-    4 d 0. 0.5 0.136 1.  0 d