data_1011070
_chemical_name_systematic          'Mercury(I) bromide'
_chemical_name_mineral             'Kuzminite'
_chemical_formula_structural       'Hg2 Br2'
_chemical_formula_sum              'Br2 Hg2'
_publ_section_title                'Crystal structure of the mercurous halides'
_publ_author_name                  'Havighurst, R J'
_journal_name_full
;
American Journal of Science, Serie 5(1,1921-1938)
;
_journal_coden_ASTM                AJSC5L
_journal_volume                    10
_journal_year                      1925
_journal_page_first                15
_journal_page_last                 28
_cell_length_a                     4.66
_cell_length_b                     4.66
_cell_length_c                     11.12
_cell_angle_alpha                  90
_cell_angle_beta                   90
_cell_angle_gamma                  90
_cell_volume                       241.5
_cell_formula_units_Z              2
_exptl_crystal_density_meas        7.31
_symmetry_space_group_name_H-M     'I 4/m m m'
_symmetry_Int_Tables_number        139
_symmetry_cell_setting             tetragonal
loop_
_symmetry_equiv_pos_as_xyz
  'x,y,z'
  '-x,-y,z'
  '-x,y,z'
  'x,-y,z'
  '-y,x,z'
  'y,-x,z'
  'y,x,z'
  '-y,-x,z'
  '-x,-y,-z'
  'x,y,-z'
  'x,-y,-z'
  '-x,y,-z'
  'y,-x,-z'
  '-y,x,-z'
  '-y,-x,-z'
  'y,x,-z'
  '1/2+x,1/2+y,1/2+z'
  '1/2-x,1/2-y,1/2+z'
  '1/2-x,1/2+y,1/2+z'
  '1/2+x,1/2-y,1/2+z'
  '1/2-y,1/2+x,1/2+z'
  '1/2+y,1/2-x,1/2+z'
  '1/2+y,1/2+x,1/2+z'
  '1/2-y,1/2-x,1/2+z'
  '1/2-x,1/2-y,1/2-z'
  '1/2+x,1/2+y,1/2-z'
  '1/2+x,1/2-y,1/2-z'
  '1/2-x,1/2+y,1/2-z'
  '1/2+y,1/2-x,1/2-z'
  '1/2-y,1/2+x,1/2-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
  Hg1+   1.000
  Br1-  -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   Hg1+   4 e 0. 0. 0.108 1.  0 d
  Br1   Br1-   4 e 0. 0. 0.358 1.  0 d