#------------------------------------------------------------------------------
#$Date: 2013-03-28 18:17:04 +0200 (Thu, 28 Mar 2013) $
#$Revision: 77586 $
#$URL: file:///home/coder/svn-repositories/cod/cif/1/01/09/1010938.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_1010938
loop_
_publ_author_name
'Nieuwenkamp, W'
_publ_section_title
;
Die Kristallstruktur des Tief-Cristobalits Si O2
;
_journal_coden_ASTM              ZEKGAX
_journal_name_full
;
Zeitschrift fuer Kristallographie, Kristallgeometrie, Kristallphysik,
Kristallchemie (-144,1977)
;
_journal_page_first              82
_journal_page_last               88
_journal_volume                  92
_journal_year                    1935
_chemical_compound_source        'from Eschwege, Germany'
_chemical_formula_structural     'Si O2'
_chemical_formula_sum            'O2 Si'
_chemical_name_mineral           'Cristobalite low'
_chemical_name_systematic        'Silicon oxide'
_symmetry_cell_setting           tetragonal
_symmetry_Int_Tables_number      92
_symmetry_space_group_name_H-M   'P 41 21 2'
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   4.964(5)
_cell_length_b                   4.964(5)
_cell_length_c                   6.920(5)
_cell_volume                     170.5
_exptl_crystal_density_meas      2.33
_cod_database_code               1010938
loop_
_symmetry_equiv_pos_as_xyz
x,y,z
-x,-y,1/2+z
1/2-y,1/2+x,1/4+z
1/2+y,1/2-x,3/4+z
y,x,-z
-y,-x,1/2-z
1/2-x,1/2+y,1/4-z
1/2+x,1/2-y,3/4-z
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
Si1 Si4+ 4 a 0.300(5) 0.300(5) 0. 1. 0 d
O1 O2- 8 b 0.245(5) 0.10(1) 0.175(5) 1. 0 d
loop_
_atom_type_symbol
_atom_type_oxidation_number
Si4+ 4.000
O2- -2.000