data_global
_chemical_name_mineral 'Gypsum'
loop_
_publ_author_name
'Comodi P'
'Nazzareni S'
'Zanazzi P F'
'Speziale S'
_journal_name_full 'American Mineralogist'
_journal_volume 93 
_journal_year 2008
_journal_page_first 1530
_journal_page_last 1537
_publ_section_title
;
 High-pressure behavior of gypsum: A single-crystal X-ray study
 Note: P = 0.0001 GPa
;
_database_code_amcsd 0004651
_chemical_compound_source 'Valle di Caramanico, Abruzzo, Italy'
_chemical_formula_sum 'Ca S O6 H4'
_cell_length_a 6.277
_cell_length_b 15.181
_cell_length_c 5.672
_cell_angle_alpha 90
_cell_angle_beta 114.11
_cell_angle_gamma 90
_cell_volume 493.340
_exptl_crystal_density_diffrn      2.318
_symmetry_space_group_name_H-M 'C 1 2/c 1'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  '1/2+x,1/2+y,z'
  'x,-y,1/2+z'
  '1/2+x,1/2-y,1/2+z'
  '-x,y,1/2-z'
  '1/2-x,1/2+y,1/2-z'
  '-x,-y,-z'
  '1/2-x,1/2-y,-z'
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_U_iso_or_equiv
Ca   0.00000   0.17050   0.25000   0.01170
S   0.00000   0.32727   0.75000   0.00990
O1   0.08319   0.27218   0.59103   0.01690
O2   0.19997   0.38195   0.91298   0.01690
OW  -0.20823   0.06826  -0.07831   0.02410
H1  -0.25800   0.08700  -0.23400   0.03300
H2  -0.24400   0.02000  -0.07700   0.04400

