data_global
_chemical_name_mineral 'Calomel'
loop_
_publ_author_name
'Calos N J'
'Kennard C H L'
'Davis R L'
_journal_name_full 'Zeitschrift fur Kristallographie'
_journal_volume 187 
_journal_year 1989
_journal_page_first 305
_journal_page_last 307
_publ_section_title
;
 The structure of calomel, Hg2Cl2, derived from neutron powder data
;
_database_code_amcsd 0010993
_chemical_formula_sum 'Hg Cl'
_cell_length_a 4.4795
_cell_length_b 4.4795
_cell_length_c 10.9054
_cell_angle_alpha 90
_cell_angle_beta 90
_cell_angle_gamma 90
_cell_volume 218.827
_exptl_crystal_density_diffrn      7.165
_symmetry_space_group_name_H-M 'I 4/m m m'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  '1/2+x,1/2+y,1/2+z'
  '-y,-x,z'
  '1/2-y,1/2-x,1/2+z'
  'y,x,-z'
  '1/2+y,1/2+x,1/2-z'
  'y,-x,-z'
  '1/2+y,1/2-x,1/2-z'
  '-y,x,z'
  '1/2-y,1/2+x,1/2+z'
  'x,-y,z'
  '1/2+x,1/2-y,1/2+z'
  '-x,y,-z'
  '1/2-x,1/2+y,1/2-z'
  'x,y,-z'
  '1/2+x,1/2+y,1/2-z'
  '-x,-y,z'
  '1/2-x,1/2-y,1/2+z'
  'y,x,z'
  '1/2+y,1/2+x,1/2+z'
  '-y,-x,-z'
  '1/2-y,1/2-x,1/2-z'
  '-y,x,-z'
  '1/2-y,1/2+x,1/2-z'
  'y,-x,z'
  '1/2+y,1/2-x,1/2+z'
  '-x,y,z'
  '1/2-x,1/2+y,1/2+z'
  'x,-y,-z'
  '1/2+x,1/2-y,1/2-z'
  '-x,-y,-z'
  '1/2-x,1/2-y,1/2-z'
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
Hg   0.00000   0.00000   0.11900
Cl   0.00000   0.00000   0.33560
loop_
_atom_site_aniso_label
_atom_site_aniso_U_11
_atom_site_aniso_U_22
_atom_site_aniso_U_33
_atom_site_aniso_U_12
_atom_site_aniso_U_13
_atom_site_aniso_U_23
Hg 0.00010 0.00010 0.42777 0.00000 0.00000 0.00000
Cl 0.05693 0.05693 -0.02410 0.00000 0.00000 0.00000