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#$Date: 2013-05-05 17:21:46 +0300 (Sun, 05 May 2013) $
#$Revision: 85285 $
#$URL: file:///home/coder/svn-repositories/cod/cif/9/00/15/9001581.cif $
#------------------------------------------------------------------------------
#
# This file is available in the Crystallography Open Database (COD),
# http://www.crystallography.net/. The original data for this entry
# were provided the American Mineralogist Crystal Structure Database,
# http://rruff.geo.arizona.edu/AMS/amcsd.php
#
# The file may be used within the scientific community so long as
# proper attribution is given to the journal article from which the
# data were obtained.
#
data_9001581
loop_
_publ_author_name
'Downs, R. T.'
'Palmer, D. C.'
_publ_section_title
;
 The pressure behavior of alpha cristobalite
 P = 1.05 GPa
;
_journal_name_full               'American Mineralogist'
_journal_page_first              9
_journal_page_last               14
_journal_volume                  79
_journal_year                    1994
_chemical_formula_sum            'O2 Si'
_chemical_name_mineral           Cristobalite
_space_group_IT_number           92
_symmetry_space_group_name_Hall  'P 4abw 2nw'
_symmetry_space_group_name_H-M   'P 41 21 2'
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_length_a                   4.8757
_cell_length_b                   4.8757
_cell_length_c                   6.7163
_cell_volume                     159.663
_diffrn_ambient_pressure         1.05e+06
_exptl_crystal_density_diffrn    2.500
_[local]_cod_chemical_formula_sum_orig 'Si O2'
_cod_database_code               9001581
loop_
_symmetry_equiv_pos_as_xyz
x,y,z
y,x,-z
1/2-y,1/2+x,1/4+z
1/2-x,1/2+y,1/4-z
-x,-y,1/2+z
-y,-x,1/2-z
1/2+y,1/2-x,3/4+z
1/2+x,1/2-y,3/4-z
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_U_iso_or_equiv
Si 0.31250 0.31250 0.00000 0.00646
O 0.23560 0.12690 0.19040 0.01418