data_global
_chemical_name_mineral 'Anhydrite'
loop_
_publ_author_name
'Cheng G'
'Zussman J'
_journal_name_full 'Acta Crystallographica'
_journal_volume 16 
_journal_year 1963
_journal_page_first 767
_journal_page_last 769
_publ_section_title
;
 The crystal structure of anhydrite (CaSO4)
;
_database_code_amcsd 0020853
_chemical_compound_source 'Madagascar'
_chemical_formula_sum 'Ca S O4'
_cell_length_a 6.991
_cell_length_b 6.996
_cell_length_c 6.238
_cell_angle_alpha 90
_cell_angle_beta 90
_cell_angle_gamma 90
_cell_volume 305.095
_exptl_crystal_density_diffrn      2.964
_symmetry_space_group_name_H-M 'A m m a'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  'x,1/2+y,1/2+z'
  '1/2+x,y,-z'
  '1/2+x,1/2+y,1/2-z'
  '1/2-x,-y,z'
  '1/2-x,1/2-y,1/2+z'
  'x,-y,z'
  'x,1/2-y,1/2+z'
  '-x,y,-z'
  '-x,1/2+y,1/2-z'
  '1/2-x,y,z'
  '1/2-x,1/2+y,1/2+z'
  '1/2+x,-y,-z'
  '1/2+x,1/2-y,1/2-z'
  '-x,-y,-z'
  '-x,1/2-y,1/2-z'
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_U_iso_or_equiv
Ca   0.75000   0.00000   0.34600   0.00887
S   0.25000   0.00000   0.15500   0.00887
O1   0.25000   0.17100   0.01500   0.01140
O2   0.08000   0.00000   0.29800   0.01393