#------------------------------------------------------------------------------
#$Date: 2012-02-28 14:14:52 +0200 (Tue, 28 Feb 2012) $
#$Revision: 35911 $
#$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
_chemical_name_systematic          'Silicon oxide'
_chemical_name_mineral             'Cristobalite low'
_chemical_compound_source          'from Eschwege, Germany'
_chemical_formula_structural       'Si O2'
_chemical_formula_sum              'O2 Si'
_publ_section_title
;
Die Kristallstruktur des Tief-Cristobalits Si O2
;
loop_
_publ_author_name                  'Nieuwenkamp, W'
_journal_name_full
;
Zeitschrift fuer Kristallographie, Kristallgeometrie, Kristallphysik,
Kristallchemie (-144,1977)
;
_journal_coden_ASTM                ZEKGAX
_journal_volume                    92
_journal_year                      1935
_journal_page_first                82
_journal_page_last                 88
_cell_length_a                     4.964(5)
_cell_length_b                     4.964(5)
_cell_length_c                     6.920(5)
_cell_angle_alpha                  90
_cell_angle_beta                   90
_cell_angle_gamma                  90
_cell_volume                       170.5
_cell_formula_units_Z              4
_exptl_crystal_density_meas        2.33
_symmetry_space_group_name_H-M     'P 41 21 2'
_symmetry_Int_Tables_number        92
_symmetry_cell_setting             tetragonal
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_type_symbol
_atom_type_oxidation_number
  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
  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
_cod_database_code 1010938