#------------------------------------------------------------------------------
#$Date: 2024-05-02 12:48:35 +0200 (Thu 02 de May de 2024) $
#$Revision: 291455 $
#$URL: svn://www.crystallography.net/cod/cif/9/00/69/9006968.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_9006968
loop_
_publ_author_name
'Graetsch, H.'
_publ_section_title
;
 X-ray powder diffraction study on the modulated high temperature forms
 of SiO2 tridymite between 110 and 220 C
 Sample: superstructure, T = 115 C
;
_journal_name_full               'Physics and Chemistry of Minerals'
_journal_page_first              313
_journal_page_last               321
_journal_paper_doi               10.1007/s002690100160
_journal_volume                  28
_journal_year                    2001
_chemical_compound_source        Synthetic
_chemical_formula_sum            'O2 Si'
_chemical_name_mineral           Tridymite
_space_group_IT_number           19
_symmetry_space_group_name_Hall  'P 2ac 2ab'
_symmetry_space_group_name_H-M   'P 21 21 21'
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_length_a                   26.1753
_cell_length_b                   4.98437
_cell_length_c                   8.2006
_cell_formula_units_Z            24
_cell_volume                     1069.911
_database_code_amcsd             0008553
_diffrn_ambient_temperature      388.15
_exptl_crystal_density_diffrn    2.238
_cod_original_formula_sum        'Si O2'
_cod_database_code               9006968
loop_
_space_group_symop_operation_xyz
x,y,z
-x,1/2+y,1/2-z
1/2+x,1/2-y,-z
1/2-x,-y,1/2+z
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_U_iso_or_equiv
Si1 0.13890 0.51100 0.69490 0.03730
Si2 0.14000 0.39100 0.32920 0.03730
Si3 0.19440 0.88800 0.19930 0.03730
Si4 0.19480 0.01900 0.83020 0.03730
Si5 0.02870 0.39500 0.18670 0.03730
Si6 0.02830 0.51000 0.81580 0.03730
O1 0.19660 -0.04300 0.01530 0.06020
O2 0.14910 0.45700 0.51030 0.06020
O3 0.08230 0.42900 0.27780 0.06020
O4 0.08140 0.56800 0.72990 0.06020
O5 0.25020 0.08000 0.77040 0.06020
O6 0.15710 0.26000 0.80020 0.06020
O7 0.17570 0.58300 0.22620 0.06020
O8 0.15700 0.08700 0.29020 0.06020
O9 0.17290 0.76600 0.73300 0.06020
O10 0.46340 0.54100 0.50210 0.06020
O11 0.49060 0.90500 0.72340 0.06020
O12 0.49600 0.72600 0.21240 0.06020
loop_
_cod_related_entry_id
_cod_related_entry_database
_cod_related_entry_code
1 AMCSD 0008553
