data_global
_chemical_name 'Dickite'
loop_
_publ_author_name
'Dera P'
'Prewitt C T'
'Japel S'
'Bish D L'
'Johnston C T'
_journal_name_full "American Mineralogist"
_journal_volume 88 
_journal_year 2003
_journal_page_first 1428
_journal_page_last 1435
_publ_section_title
;
 Pressure-controlled polytypism in hydrous layered materials
 Sample: Low pressure dickite at P = 0.1 MPa	
;
_chemical_formula_sum 'Si2 Al2 O9 H4'
_cell_length_a 5.161
_cell_length_b 8.960
_cell_length_c 14.459
_cell_angle_alpha 90
_cell_angle_beta 96.77
_cell_angle_gamma 90
_cell_volume 663.959
_symmetry_space_group_name_H-M 'C 1 c 1'
loop_
_symmetry_equiv_pos_as_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'
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_Uiso_or_equiv
Si1   0.00880   0.40100   0.03240   0.01200
Si2  -0.00350   0.07220   0.03150   0.01000
Al1   0.91260   0.25230   0.22330   0.01600
Al2   0.41840   0.41760   0.22260   0.01800
O1   0.95620   0.23800   0.98640   0.01700
O2   0.25480   0.47140   0.98560   0.01800
O3   0.76360   0.50580   0.99910   0.01700
O4   0.07890   0.39080   0.14280   0.02100
O5   0.00250   0.08070   0.14430   0.01200
O-h1   0.58500   0.27470   0.14880   0.02200
O-h2   0.24320   0.27800   0.28660   0.01800
O-h3   0.25250   0.89320   0.28880   0.01500
O-h4   0.32340   0.58370   0.28630   0.02100
H1   0.57000   0.17300   0.15200   0.02600
H2   0.30700   0.26000   0.34600   0.02200
H3   0.25000   0.99000   0.30500   0.01800
H4   0.27000   0.58800   0.34200   0.02600