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#$Date: 2008-01-14 00:15:36 +0200 (Mon, 14 Jan 2008) $
#$Revision: 14 $
#$URL: file:///home/coder/svn-repositories/cod/cif/1/1010541.cif $
#------------------------------------------------------------------------------
#
# This file is available in the Crystallography Open Database (COD),
# http://www.crystallography.net/
#
# All data on this site have been placed in the public domain by the
# contributors.
#
data_1010541
_chemical_name_systematic          'Triberyllium dialuminium catena-silicate'
_chemical_formula_structural       'Be3 Al2 Si6 O18'
_chemical_formula_sum              'Al2 Be3 O18 Si6'
_publ_section_title
;
The Structure of Beryl, Be~3~ Al~2~ Si~6~ O~18~
;
_publ_author_name                  'Bragg, W L'
_journal_name_full
;
Proceedings of the Royal Society of London, Series A: Mathematical and
Physical Sciences (76,1906-)
;
_journal_coden_ASTM                PRLAAZ
_journal_volume                    111
_journal_year                      1926
_journal_page_first                691
_journal_page_last                 714
_cell_length_a                     9.21(1)
_cell_length_b                     9.21(1)
_cell_length_c                     9.17(1)
_cell_angle_alpha                  90
_cell_angle_beta                   90
_cell_angle_gamma                  120
_cell_volume                       673.6
_cell_formula_units_Z              2
_symmetry_space_group_name_H-M     'P 6/m c c S'
_symmetry_Int_Tables_number        192
_symmetry_cell_setting             hexagonal
loop_
_symmetry_equiv_pos_as_xyz
  'x,y,z'
  '-x,-y,z'
  'y-x,-x,z'
  'x-y,x,z'
  '-y,x-y,z'
  'y,y-x,z'
  'y,x,-z'
  '-y,-x,-z'
  '-x,y-x,-z'
  'x,x-y,-z'
  'x-y,-y,-z'
  'y-x,y,-z'
  'x,y,1/2-z'
  '-x,-y,1/2-z'
  'y-x,-x,1/2-z'
  'x-y,x,1/2-z'
  '-y,x-y,1/2-z'
  'y,y-x,1/2-z'
  'y,x,1/2+z'
  '-y,-x,1/2+z'
  '-x,y-x,1/2+z'
  'x,x-y,1/2+z'
  'x-y,-y,1/2+z'
  'y-x,y,1/2+z'
loop_
_atom_type_symbol
_atom_type_oxidation_number
  Al3+   3.000
  Be2+   2.000
  Si4+   4.000
  O2-   -2.000
loop_
_atom_site_label
_atom_site_type_symbol
_atom_site_symmetry_multiplicity
_atom_site_Wyckoff_symbol
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_occupancy
_atom_site_attached_hydrogens
_atom_site_calc_flag
  Al1   Al3+   4 d 0.6667 0.3333 0. 1.  0 d
  Be1   Be2+   6 g 0.5 0. 0. 1.  0 d
  Si1   Si4+  12 l 0.39 0.12 0.25 1.  0 d
  O1    O2-   24 m 0.48 0.15 0.1 1.  0 d
  O2    O2-   12 l 0.3 0.24 0.25 1.  0 d