data_global
_chemical_name_mineral 'Alum-(Na)'
loop_
_publ_author_name
'Larson A C'
'Cromer D T'
_journal_name_full 'Acta Crystallographica'
_journal_volume 22 
_journal_year 1967
_journal_page_first 793
_journal_page_last 800
_publ_section_title
;
 Refinement of the alum structures. III. X-ray study of the a alums,
 K, Rb and NH4Al(SO4)2*12H2O
;
_database_code_amcsd 0019047
_chemical_compound_source 'Synthetic'
_chemical_formula_sum 'Rb Al S2 O20 H24'
_cell_length_a 12.243
_cell_length_b 12.243
_cell_length_c 12.243
_cell_angle_alpha 90
_cell_angle_beta 90
_cell_angle_gamma 90
_cell_volume 1835.116
_exptl_crystal_density_diffrn      1.885
_symmetry_space_group_name_H-M 'P a 3'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  '1/2+z,x,1/2-y'
  'z,1/2-x,1/2+y'
  '1/2-z,1/2+x,y'
  '-z,-x,-y'
  '1/2+y,1/2-z,-x'
  '1/2-y,-z,1/2+x'
  '-y,1/2+z,1/2-x'
  'y,z,x'
  'x,1/2-y,1/2+z'
  '1/2-x,1/2+y,z'
  '1/2+x,y,1/2-z'
  '-x,-y,-z'
  '1/2-z,-x,1/2+y'
  '-z,1/2+x,1/2-y'
  '1/2+z,1/2-x,-y'
  'z,x,y'
  '1/2-y,1/2+z,x'
  '1/2+y,z,1/2-x'
  'y,1/2-z,1/2+x'
  '-y,-z,-x'
  '-x,1/2+y,1/2-z'
  '1/2+x,1/2-y,-z'
  '1/2-x,-y,1/2+z'
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
Rb   0.50000   0.50000   0.50000
Al   0.00000   0.00000   0.00000
S   0.31270   0.31270   0.31270
O(1)   0.24710   0.24710   0.24710
O(2)   0.31720   0.26390   0.42370
Wat(1)   0.04510   0.14060   0.29750
Wat(2)   0.01730  -0.01480   0.15540
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
Rb 0.03797 0.03797 0.03797 0.02354 0.02354 0.02354
Al 0.01898 0.01898 0.01898 0.00835 0.00835 0.00835
S 0.02126 0.02126 0.02126 -0.00456 -0.00456 -0.00456
O(1) 0.08884 0.08884 0.08884 0.04252 0.04252 0.04252
O(2) 0.04404 0.09568 0.02886 0.04860 -0.01215 0.05467
Wat(1) 0.02961 0.02278 0.01215 0.00076 -0.00076 0.00076
Wat(2) 0.00835 0.03037 0.00987 0.00456 0.01139 -0.01139