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#$Date: 2008-01-26 15:05:32 +0200 (Sat, 26 Jan 2008) $
#$Revision: 19 $
#$URL: file:///home/coder/svn-repositories/cod/cif/9/9005270.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_9005270
_chemical_name 'Tridymite'
loop_
_publ_author_name
'Graetsch H'
'Topalovic-Dierdorf I'
_journal_name_full "European Journal of Mineralogy"
_journal_volume 8
_journal_year 1996
_journal_page_first 103
_journal_page_last 113
_publ_section_title
;
 29Si MAS NMR spectrum and superstructure of modulated tridymite L3-To(MX-1)
 Sample: average crystal structure
;
_chemical_formula_sum 'Si O2'
_cell_length_a 5.007
_cell_length_b 8.6004
_cell_length_c 8.2169
_cell_angle_alpha 90
_cell_angle_beta 91.512
_cell_angle_gamma 90
_cell_volume 353.715
_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   0.07640   0.30730   0.21080   0.05200
Si2   0.07730   0.35920   0.83520   0.05200
O1   0.28850   0.75300   0.25340   0.04400
O2   0.14400   0.46470   0.30820   0.08500
O3   0.28840   0.17970   0.27030   0.13800
O4   0.58260   0.16680   0.51980   0.18800