data_9003989
_chemical_name 'Sillimanite'
loop_
_publ_author_name
'Burt J B'
'Ross N L'
'Angel R J'
'Koch M'
_journal_name_full "American Mineralogist"
_journal_volume 91
_journal_year 2006
_journal_page_first 319
_journal_page_last 326
_publ_section_title
;
 Equations of state and structures of andalusite
 to 9.8 GPa and sillimanite to 8.5 GPa
 Locality: Okkamitiya Sabaragamuiwa province, Sri Lanka
 Sample: P = 7.663 GPa
;
_chemical_formula_sum 'Al2 Si O5'
_cell_length_a 7.3717
_cell_length_b 7.5243
_cell_length_c 5.72421
_cell_angle_alpha 90
_cell_angle_beta 90
_cell_angle_gamma 90
_cell_volume 317.504
_symmetry_space_group_name_H-M 'P b n m'
loop_
_symmetry_equiv_pos_as_xyz
  'x,y,z'
  'x,y,1/2-z'
  '-x,-y,1/2+z'
  '1/2+x,1/2-y,1/2+z'
  '1/2-x,1/2+y,1/2-z'
  '1/2-x,1/2+y,z'
  '1/2+x,1/2-y,-z'
  '-x,-y,-z'
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_Uiso_or_equiv
Al1   0.00000   0.00000   0.00000   0.00317
Al2   0.13970   0.33890   0.25000   0.00405
Si   0.15500   0.33630   0.75000   0.00317
OA   0.36420   0.41170   0.75000   0.00279
OB   0.35500   0.44110   0.25000   0.00697
OC   0.47230   0.00330   0.75000   0.01064
OD   0.12850   0.21670   0.51480   0.00595