data_global
_chemical_name_mineral 'Topaz'
loop_
_publ_author_name
'Chen J'
'Lager G A'
'Kunz M'
'Hansen T C'
'Ulmer P'
_journal_name_full 'Acta Crystallographica, Section E'
_journal_volume 61 
_journal_year 2005
_journal_page_first i253
_journal_page_last i255
_publ_section_title
;
 A Rietveld refinement using neutron powder diffraction data of a
 fully deuterated topaz, Al2SiO4(OD)2
;
_database_code_amcsd 0010464
_chemical_compound_source 'Synthetic'
_chemical_formula_sum 'Al2 Si O6 D2'
_cell_length_a 4.72820
_cell_length_b 8.9320
_cell_length_c 8.4309
_cell_angle_alpha 90
_cell_angle_beta 90
_cell_angle_gamma 90
_cell_volume 356.056
_exptl_crystal_density_diffrn      3.397
_symmetry_space_group_name_H-M 'P b n m'
loop_
_space_group_symop_operation_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_occupancy
_atom_site_U_iso_or_equiv
Al   0.90710   0.13250   0.07790   1.00000   0.00300
Si   0.40320   0.94040   0.25000   1.00000   0.00020
O1   0.70800   0.02600   0.25000   1.00000   0.00150
O2   0.44310   0.75510   0.25000   1.00000   0.00170
O3   0.21290   0.99220   0.09460   1.00000   0.00310
O4   0.59170   0.25040   0.06610   1.00000   0.00480
D1   0.44000   0.18580   0.10310   0.50000   0.04500
D2   0.53200   0.28110   0.16750   0.50000   0.04800