data_global
_chemical_name_mineral 'Bassanite'
loop_
_publ_author_name
'Abriel W'
'Nesper R'
_journal_name_full 'Zeitschrift fur Kristallographie'
_journal_volume 205 
_journal_year 1993
_journal_page_first 99
_journal_page_last 113
_publ_section_title
;
 Bestimmung der Kristallstruktur von CaSO4(H2O)0.5 mit
 Rontgenbeugungsmethoden und mit Potentialprofil-Rechnungen
;
_database_code_amcsd 0019827
_chemical_compound_source 'Synthetic'
_chemical_formula_sum 'Ca2 S2 O9 H2'
_cell_length_a 12.0275
_cell_length_b 6.9312
_cell_length_c 12.6919
_cell_angle_alpha 90
_cell_angle_beta 90.18
_cell_angle_gamma 90
_cell_volume 1058.055
_exptl_crystal_density_diffrn      2.734
_symmetry_space_group_name_H-M 'I 1 2 1'
loop_
_space_group_symop_operation_xyz
  '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
Ca1   0.00000   0.45530   0.00000
Ca2   0.00000   0.45530   0.50000
Ca3   0.27240   0.27240   0.16670
Ca4   0.72760   0.27240   0.33330
S1   0.72480   0.27520   0.08330
S2   0.00000   0.44960   0.25000
S3   0.27520   0.27520   0.41670
O1   0.12910   0.72600   0.01730
O2   0.12910   0.72600   0.51730
O3   0.29850   0.44350   0.85070
O4   0.29850   0.44350   0.35070
O5   0.07250   0.33060   0.18400
O6   0.07250   0.33060   0.68400
O7   0.25380   0.61850   0.15560
O8   0.25380   0.61850   0.65560
O9   0.18240   0.31020   0.98890
O10   0.18240   0.31020   0.48890
O11   0.06390   0.57140   0.82220
O12   0.06390   0.57140   0.32220
Ow1   0.50000   0.59850   0.00000
Ow2   0.54930   0.45080   0.33330
H1   0.42800   0.67100   0.00000
H2   0.55000   0.30700   0.33300
H3   0.62100   0.52300   0.33300